Getting XmlAnyTypeImpl rather than the expected class

Hi All

Within Apache POI, we're using xmlbeans to compile the Microsoft xsds for the 
OOXML file format to something usable. We produce two jars of the compiled 
XSDs, one with the full set, and one with just the key classes and .xsb files.

This seemed to have been working fine, but we've found that in some cases, when 
using the smaller jar, certain XmlObjects are coming back as XmlAnyTypeImpl, 
rather than the expected class. An attempt to convert them to the right object 
via changeType blows up with a ClassCastException

I'm guessing that we're not copying a crucial class or resource over into the 
smaller jar file. However, I can't seem to find the bit of XmlBeans that is 
responsible for this sort of thing, to figure out what the missing file is.

Any chance someone knows the area of code I should be looking at?

For anyone interested, the problem class is 
org.openxmlformats.schemas.drawingml.x2006.picture.CTPicture which is stored in 
a
org.openxmlformats.schemas.drawingml.x2006.main.CTGraphicalObjectData

The jar files are available from
http://mirrors.ibiblio.org/pub/mirrors/maven2/org/apache/poi/ooxml-schemas/1.1/ooxml-schemas-1.1.jar
for the full one, and the minimal one from
http://mirrors.ibiblio.org/pub/mirrors/maven2/org/apache/poi/poi-ooxml-schemas/3.7-beta2/poi-ooxml-schemas-3.7-beta2.jar

Thanks
Nick