I'm not aware of anything that would remove that... all we do is to forward the message again.
Maybe you are hitting a bug. Can you make sure you don't have any transformers or anything doing that?
If you can debug BridgeImpl...
Add BridgeImpl to do trace log (FINEST if you are using standalone), and look at what's being sent before on this:
log.trace("XXX going to send message " + message);
BTW: I just removed the XXX from the code :-) It was a mistake.. I sometims will place XXX on the traces I need while debugging stuff.