NPE while initializing a type system w/ a type that extends an a complex type from a different type system

This bug occurs w/ v1.0.3, as well as w/ v1 SVN top-of-tree.

It occurs in the following situation:

• schema A defines type A, which is a complex type containing a sequence of one anon complex types. schema A is xmlbeans-compiled into A.jar

• schema B contains type B which extends type A. it also defines an element of type B. schema B is compiled into B.jar, passing A.jar into scomp's classpath option

• B.xml is an instance doc containing a document element of type B

• when we try to parse() B.xml, w/ A.jar and B.jar in the JVM classpath, we get a big stack trace w/ a root cause of an NPE during type system initialization (see the attached stack trace)