boolean "1" normalized to "true" breaks pattern facet validation

I was trying to declare an element with a mandatory
soap:mustUnderstand="1" attribute, like so:

<attribute ref="soap:mustUnderstand" use="required" fixed="1"/>

I get the following error when parsing the schema from Xerces 2.6.2:

  Value 'true' is not facet-valid with respect to pattern '0|1'

But my .xsd doesn't say "true" anywhere -- it says "1".

This was in the context of a schema that referenced SOAP, but I boiled
it down to the following trivial example:

<schema xmlns="http://www.w3.org/2001/XMLSchema";
        xmlns:tns="http://example.com";
        targetNamespace="http://example.com";>

  <attribute name="mustUnderstand" >    
    <simpleType>
      <restriction base='boolean'>
        <pattern value='0|1' />
      </restriction>
    </simpleType>
  </attribute>
  
  <element name="Test">
    <complexType>
      <attribute ref="tns:mustUnderstand" use="required" fixed="1"/>
    </complexType>
  </element>

</schema>

Then we get the following error from the XMLGrammarBuilder sample:

$ java xni.XMLGrammarBuilder -f -a test-default.xsd
[Error] test-default.xsd:16:69: cvc-pattern-valid: Value 'true' is not
 facet-valid with respect to pattern '0|1' for type 'null'.
[Error] test-default.xsd:16:69: a-props-correct.2: Invalid value
 constraint value '1' in attribute 'mustUnderstand'.


If I change each "1" to "true", and each "0" to "false", this works
fine and has the desired effect.

This seems to be a bug in Xerces.  I didn't see anything like it in
Jira.  Has anyone run into this before?

Thanks,

Steve



-- 
Steven C. Ihde <sihde@xxxxxxxxxxxxxxx>
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