CSDL version 3.0 allows inheritance for complex types, see http://msdn.microsoft.com/en-us/library/dd541510(v=prot.10). This is missing from the contribution.
CSDL version 3.0 allows inheritance for complex types, see http://msdn.microsoft.com/en-us/library/dd541510(v=prot.10). This is missing from the contribution.