Hmm curious. I've had a look through the ObexListener code files and can't see it sending a Forbidden response. I wonder if the built-in server is still running, at least partly and picking up, but then discarding, the incoming connection.
Can you run the SdpBrowser app (either on one of the PCs on one the phone and do a "all services over l2cap" lookup for the phone. Do it the built-in server enabled, disabled without your server running, and with your server running. Check that the ObexOjectPush service disappears in the second case.
Alan J. McFarlane
http://www.alanjmcf.me.uk/
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