Jelly Errors / Debug Advice?

I'm venturing into writing plugins for the first time, so I'm just starting to learn how the global.jelly and config.jelly's work. This is my first time playing with jelly so its all a learning experience for me. 

After activating the HelloWorld plugin, I've noticed that when I go into the Job Configuration screen, it renders correctly - but I sometimes see the error below depending on what I've done to the file. For example, if I comment out the body of the xml so its just the opening and closing j:jelly tag, or if I actually remove the 
configure.jelly file altogether. I only know the problem has to do with this file because of the screen it happens on and when I see errors on stderr (and because I'm only changing one thing at a time)

From the error, I really don't know what is wrong - or what file is there. I can deduce the file with the problem through the means above, but I haven't yet learned what is expected. I'm guessing it must be the missing f:entry tag. I'll figure it out shortly, but I'm wondering if there are some techniques to better debug this kind of stuff that you've developed through your experience in creating the built-in jelly components?

Thanks,

2007-01-25 23:38:28.087::INFO:  Started SelectChannelConnector @ 0.0.0.0:8080
java.lang.NullPointerException
        at hudson.Functions.isMultiline(Functions.java
:312)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke
(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:585)
        at org.apache.commons.jexl.util.introspection.UberspectImpl$VelMethodImpl.invoke(UberspectImpl.java:255)
        at org.apache.commons.jexl.parser.ASTMethod.execute(ASTMethod.java:104)
        at org.apache.commons.jexl.parser.ASTReference.execute(ASTReference.java:82)
        at org.apache.commons.jexl.parser.ASTReference.value
(ASTReference.java:56)
        at org.apache.commons.jexl.parser.ASTReferenceExpression.value(ASTReferenceExpression.java:50)
        at org.apache.commons.jexl.ExpressionImpl.evaluate(ExpressionImpl.java:79)
        at 
org.apache.commons.jelly._expression_.jexl.JexlExpression.evaluate(JexlExpression.java:69)
        at org.apache.commons.jelly._expression_.ExpressionSupport.evaluateRecurse(ExpressionSupport.java:61)
        at org.apache.commons.jelly._expression_.ExpressionSupport.evaluateAsBoolean
(ExpressionSupport.java:71)
        at org.apache.commons.jelly.tags.core.WhenTag.doTag(WhenTag.java:44)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run
(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.ChooseTag.doTag(ChooseTag.java:38)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag
(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag
(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag
(InvokeBodyTag.java:91)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run
(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run
(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag
(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag
(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.kohsuke.stapler.jelly.IncludeTag.doTag(IncludeTag.java:83)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag(InvokeBodyTag.java:91)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag
(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.ForEachTag.doTag
(ForEachTag.java:150)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag
(InvokeBodyTag.java:91)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag
(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag
(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.kohsuke.stapler.jelly.IncludeTag.doTag
(IncludeTag.java:83)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag
(InvokeBodyTag.java:91)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run
(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run
(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag
(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag(InvokeBodyTag.java:91)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.IfTag.doTag
(IfTag.java:42)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag
(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag
(InvokeBodyTag.java:91)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run
(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run
(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag
(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run
(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run
(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag
(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag
(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.kohsuke.stapler.jelly.JellyClassTearOff.invokeScript(JellyClassTearOff.java:65)
        at org.kohsuke.stapler.MetaClass$3.dispatch
(MetaClass.java:100)
        at org.kohsuke.stapler.Stapler.invoke(Stapler.java:224)
        at org.kohsuke.stapler.MetaClass$9.doDispatch(MetaClass.java:207)
        at org.kohsuke.stapler.NameBasedDispatcher.dispatch
(NameBasedDispatcher.java:30)
        at org.kohsuke.stapler.Stapler.invoke(Stapler.java:224)
        at org.kohsuke.stapler.Stapler.invoke(Stapler.java:169)
        at org.kohsuke.stapler.Stapler.service(Stapler.java
:68)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
        at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:491)
        at org.mortbay.jetty.servlet.ServletHandler.handle
(ServletHandler.java:367)
        at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:185)
        at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:181)
        at org.mortbay.jetty.handler.ContextHandler.handle
(ContextHandler.java:689)
        at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:391)
        at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:146)
        at 
org.mortbay.jetty.handler.HandlerCollection.handle(HandlerCollection.java:114)
        at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:139)
        at org.mortbay.jetty.Server.handle(Server.java
:285)
        at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:457)
        at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:751)
        at org.mortbay.jetty.HttpParser.parseNext
(HttpParser.java:500)
        at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:209)
        at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:357)
        at org.mortbay.io.nio.SelectChannelEndPoint.run
(SelectChannelEndPoint.java:329)
        at org.mortbay.thread.BoundedThreadPool$PoolThread.run(BoundedThreadPool.java:475)
[WARN] JexlExpression - -Caught exception evaluating: h.isMultiline(attrs.value). Reason: java.lang.NullPointerException
 <java.lang.NullPointerException>
java.lang.NullPointerException
        at hudson.Functions.isMultiline(Functions.java:312)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at 
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke
(Method.java:585)
        at org.apache.commons.jexl.util.introspection.UberspectImpl$VelMethodImpl.invoke(UberspectImpl.java:255)
        at org.apache.commons.jexl.parser.ASTMethod.execute(ASTMethod.java:104)
        at 
org.apache.commons.jexl.parser.ASTReference.execute(ASTReference.java:82)
        at org.apache.commons.jexl.parser.ASTReference.value(ASTReference.java:56)
        at org.apache.commons.jexl.parser.ASTReferenceExpression.value
(ASTReferenceExpression.java:50)
        at org.apache.commons.jexl.ExpressionImpl.evaluate(ExpressionImpl.java:79)
        at org.apache.commons.jelly._expression_.jexl.JexlExpression.evaluate(JexlExpression.java:69)
        at org.apache.commons.jelly._expression_.ExpressionSupport.evaluateRecurse(ExpressionSupport.java:61)
        at org.apache.commons.jelly._expression_.ExpressionSupport.evaluateAsBoolean(ExpressionSupport.java:71)
        at org.apache.commons.jelly.tags.core.WhenTag.doTag(WhenTag.java:44)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java
:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.ChooseTag.doTag(ChooseTag.java:38)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag
(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag
(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag
(InvokeBodyTag.java:91)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run
(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run
(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag
(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag
(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.kohsuke.stapler.jelly.IncludeTag.doTag(IncludeTag.java:83)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag(InvokeBodyTag.java:91)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag
(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.ForEachTag.doTag
(ForEachTag.java:150)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag
(InvokeBodyTag.java:91)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag
(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag
(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.kohsuke.stapler.jelly.IncludeTag.doTag
(IncludeTag.java:83)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag
(InvokeBodyTag.java:91)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run
(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run
(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag
(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag(InvokeBodyTag.java:91)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.IfTag.doTag
(IfTag.java:42)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag
(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag
(InvokeBodyTag.java:91)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run
(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run
(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag
(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody
(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run
(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.impl.StaticTag.doTag(StaticTag.java:65)
        at org.apache.commons.jelly.impl.StaticTagScript.run
(StaticTagScript.java:112)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag
(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.apache.commons.jelly.impl.DynamicTag.doTag(DynamicTag.java:80)
        at org.apache.commons.jelly.impl.TagScript.run
(TagScript.java:262)
        at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
        at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:186)
        at org.apache.commons.jelly.tags.core.JellyTag.doTag
(JellyTag.java:45)
        at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:262)
        at org.kohsuke.stapler.jelly.JellyClassTearOff.invokeScript(JellyClassTearOff.java:65)
        at org.kohsuke.stapler.MetaClass$3.dispatch
(MetaClass.java:100)
        at org.kohsuke.stapler.Stapler.invoke(Stapler.java:224)
        at org.kohsuke.stapler.MetaClass$9.doDispatch(MetaClass.java:207)
        at org.kohsuke.stapler.NameBasedDispatcher.dispatch
(NameBasedDispatcher.java:30)
        at org.kohsuke.stapler.Stapler.invoke(Stapler.java:224)
        at org.kohsuke.stapler.Stapler.invoke(Stapler.java:169)
        at org.kohsuke.stapler.Stapler.service(Stapler.java
:68)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
        at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:491)
        at org.mortbay.jetty.servlet.ServletHandler.handle
(ServletHandler.java:367)
        at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:185)
        at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:181)
        at org.mortbay.jetty.handler.ContextHandler.handle
(ContextHandler.java:689)
        at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:391)
        at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:146)
        at 
org.mortbay.jetty.handler.HandlerCollection.handle(HandlerCollection.java:114)
        at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:139)
        at org.mortbay.jetty.Server.handle(Server.java
:285)
        at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:457)
        at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:751)
        at org.mortbay.jetty.HttpParser.parseNext
(HttpParser.java:500)
        at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:209)
        at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:357)
        at org.mortbay.io.nio.SelectChannelEndPoint.run
(SelectChannelEndPoint.java:329)
        at org.mortbay.thread.BoundedThreadPool$PoolThread.run(BoundedThreadPool.java:475)
[WARN] JexlExpression - -Caught exception evaluating: h.isMultiline(attrs.value). Reason: java.lang.NullPointerException
 <java.lang.NullPointerException>


-- 

- Eric