As a generic solution you could put schema prefixes on table names, but I suspect you would have already tried that anyways. Not sure if the issue I'll describe is the same for websphere, but just in case it is, the folliwng info might help. More relevant if you are using CMP, not necessarily relevant for anything else.
Different databases deal with JDBC catalogs in different ways. I'd argue the spec was a bit weak, but c'est la vie... things are as they are now.
Different servers sometimes deal with catalog information in different ways in different parts of the container;
JBoss is really bad that way. I'd argue that is bug, but ditto for things being the way they are.
When using multi-catalog (schema in Oracle, database or object owner in SQLServer) products with CMP, there are two
patterns of usage that can cause CMP to break, one obvious, the other less so. The obvious one is that the schema you are logging in as must have grants that allow it to see the objects in the other schema; no big surprise there. Just login as the application user via SQL*Plus, and if you can't see the objects, you know the grants are wrong.
The less obvious second situation is that if you have MULTIPLE schemas that have objects of the same type and name, then you can have situations where CMP looks in the correct schema during one state (like deployment and bean pool creation), but incorrectly in another state (like actual DML execution). If you hit that problem and schema prefixing isn't an option or doesn't work for you, the only solution I know is to alter grants to eliminate the duplicates. If all the object/name mappings are unique, the problem doesn't tend to come up.
I find people hit this problem routinely with JBoss and Oracle when they have multiple development or QA schemas in play, and slammed DBA-level grants onto everything. I've seen similar things with SQLServer, but not as often. You'll have to figure out if something comparable is happening for you with WebSphere.
[ March 09, 2006: Message edited by: Reid M. Pinchback ]