You need the DB2 client libraries only. Check out IBM's howto.

-derby

<rant>I don't know why RDBMS companies feel compelled to bury their drivers so deep under cover. You would think that they would want to distribute (and even -- egads -- open source) the drivers in a give away the razor type promotion.</rant>

Anyways, in case your DBA cannot extract the client for you, they can be found here (for now at least).