Really I am not expert in Development stuff but I hope this can help you:
ORA-31000 Resource 'string' is not an XDB schema document
Cause: The given schema URL does not refer to a registered XDB schema.
Action: Make sure the specified schema has been registered in XDB.
XML API Reference - XDK and Oracle XML DB Contents / Search / Index / PDF
XML Database Developer's Guide - Oracle XML DB Contents / Search / Index / PDF
XML Developer's Kits Guide - XDK Contents / Search / Index / PDF http://otn.oracle.com/pls/db92/db92....emark=homepage