NPE when running scomp on this schema

Please see the attached schema. If you run the following scomp on it you get the NPE below:

scomp -d classes -src src -javasource 1.5 -mx 500m schema

NPE:

Exception in thread "main" java.lang.NullPointerException
at org.apache.xmlbeans.impl.schema.SchemaTypeImpl.getIndexForLocalAttribute(SchemaTypeImpl.java:690)
at org.apache.xmlbeans.impl.schema.SchemaTypeSystemImpl$XsbReader.writeTypeData(SchemaTypeSystemImpl.java:2698)
at org.apache.xmlbeans.impl.schema.SchemaTypeSystemImpl.saveType(SchemaTypeSystemImpl.java:1439)
at org.apache.xmlbeans.impl.schema.SchemaTypeSystemImpl.saveTypesRecursively(SchemaTypeSystemImpl.java:1316)
at org.apache.xmlbeans.impl.schema.SchemaTypeSystemImpl.saveTypesRecursively(SchemaTypeSystemImpl.java:1317)
at org.apache.xmlbeans.impl.schema.SchemaTypeSystemImpl.saveTypesRecursively(SchemaTypeSystemImpl.java:1317)
at org.apache.xmlbeans.impl.schema.SchemaTypeSystemImpl.saveTypesRecursively(SchemaTypeSystemImpl.java:1317)
at org.apache.xmlbeans.impl.schema.SchemaTypeSystemImpl.save(SchemaTypeSystemImpl.java:1291)
at org.apache.xmlbeans.impl.tool.SchemaCompiler.compile(SchemaCompiler.java:1098)
at org.apache.xmlbeans.impl.tool.SchemaCompiler.main(SchemaCompiler.java:368)