WSDL+Array compilation

Hi there
I'm trying to use XmlBeans for representing complex types
in WebService interactions. So I took a simple WSDL and
compiled it and have a few questions about the result.
First, I had to manually download the XSD at
<import namespace="http://schemas.xmlsoap.org/soap/encoding/"/>
using the -dl option to scomp didn't change a thing.
Is this normal ?
Second, using a WSDL containing the following:
  <schema targetNamespace="http://com.nuance.vaf/data/services"; 
xmlns="http://www.w3.org/2
001/XMLSchema">
   <import namespace="http://schemas.xmlsoap.org/soap/encoding/"/>
   <complexType name="ArrayOfArrayOf_xsd_string">
    <complexContent>
     <restriction base="soapenc:Array">
      <attribute ref="soapenc:arrayType" wsdl:arrayType="xsd:string[][]"/>
     </restriction>
    </complexContent>
   </complexType>
  </schema>
I generated the XmlBeans classes and got a class that
properly extends the schemas.xmlsoap.org.soap.encoding.Array class.
However, this Array class has no method to add elements to it, you can
only set the attributes, despite the fact that soapenc:Array is
  <xs:group name="Array" >
    <xs:sequence>
      <xs:any namespace="##any" minOccurs="0" maxOccurs="unbounded" 
processContents="lax" 
/>
        </xs:sequence>
  </xs:group>

  <xs:element name="Array" type="tns:Array" />
  <xs:complexType name="Array" >
    <xs:annotation>
          <xs:documentation>
           'Array' is a complex type for accessors identified by position 
          </xs:documentation>
        </xs:annotation>
    <xs:group ref="tns:Array" minOccurs="0" />
    <xs:attributeGroup ref="tns:arrayAttributes" />
    <xs:attributeGroup ref="tns:commonAttributes" />
  </xs:complexType> 
So I would have expected to be able to add some elements to it.
Did I do something wrong or is it related to the partial 'substitution group'
support in XmlBeans ?
Thanks
          jog