I'm programming and MDB that reads and updates a database then sends out an HTTP Post and logs using log4j. I've read that when an MDB is configured as CMT or container managed transaction and the OnMessage method executes without errors, the transaction is implicitly commited. You can rollback the transaction by explicitly calling setRollbackOnly() or when a RuntimeException has been thrown. My worry is that after I have sent out an HTTP POST (a transaction has been completed) I would have to log a transaction completion using log4j. My problems is if log4j throws a RuntimeException thereby rolling back my transaction which shouldn't be the case. What I have done is to catch all Exceptions (and swallow them) whenever I log using log4j after I have sent out an HTTP POST succesfully (since my transaction should be complete by then). Is this a correct workaround?