JDBC adapter template does not load list of schemas from database

I am getting the following error while trying to create an Insert operation using insertSQL template 0f JDBC adapter. The operation is created but it does not load the list of schemas.
I am using webMethods 6.1 and JDBC adapter 6.0.3 and is connecting to oracle database.

Here is the exact error message
com.wm.app.b2b.server.ServiceException: [ART.114.205] Adapter Runtime (Metadata): Unable to lookup the resource domain values.
[ADA.1.321] Cannot get the list of schemas. "
(60000/600) ORA-00600: internal error code, arguments: [ttcgcshnd-1], [0], , , , , ,
ORA-00600: internal error code, arguments: [ttcgcshnd-1], [0], , , , , ,
on tables.schemaName [Ljava.lang.String;@1a3fa82
java.lang.Exception: Adapter values are not available.

The database has a large number of schemas.
Any help will be appreciated.

I recall that we had similar errors on our 6.1 server when we installed JDBC 6.0.3 using Oracle 9i.
Make sure the classes12.zip file from Oracle is at the proper directory on the designated server
at : /opt/webMethods6/IntegrationServer/lib/jars

And insure that the userid that is running the adapter has schema rights on the Oracle instance.
Also checkout url: