XA and WebLogic Server

We are trying to use XA transaction handling in a Informix 7.31.UD5 database, using Weblogic Server 6.1 SP5 as transaction manager. We have tried both JDBC 2.21.JC3 and JC4. The problem that we are running into is that we occasionally get locked rows in the database. A transaction started from WebLogic locks rows in tables involved in the transaction. This happens sometimes, not always, when a transaction is interrupted. The only way , besides restarting the database server, to solve the problem is to issue onmode -l commands until a long transaction rollback the transaction. Now to my questions: - has anybody seen this problem, that rows remain locked even if WebLogic is restarted or whatever you do except restarting the database server or forcing a long transaction ? - is anybody using WebLogic Server and XA handling with Informix, and if so does it work OK ? I have talked both with Informix/IBM support and BEA, no answers yet, would appreciate any information from the group TIA Ulf