Database Software

I want to be able to use xs:import or xs:include
when defining my schemas, but I haven't been successful
in registering a schema that uses these directives.

I either get a ORA-31000 error when using a schemaLocation from my own Web server, such as:

<xs:include schemaLocation="http://1.2.3.4/a.xsd" />

Or I get an ORA-04021 error when using a schemaLocation that points to a previously registered schema in XDB, such as:

... dbms_schema.register_schema('http://xmlns.foo.com/a') ...

then

<xs:import namespace="http://xmlns.foo.com/a"
schemaLocation="http://xmlns.foo.com/a" />

yields:

ORA-04021: timeout occurred while waiting to lock object XDB.table78_T (which is defined as a type in the http://xmlns.foo.com/a registered schema)...

Ideally, I'd like some example schemas that use xs:import as that is the directive that I'm most interested in.

Thanks,
-Darren