Transfer calls between OpenSER users w/ Asterisk Gatewaying

Hi there,

If i receive a call from an ISDN line connected to a PCI card interfacing with Asterisk and pass it to a phone registered in an OpenSER instance running in the same machine everything works as expected, however if in that phone i try to transfer the call to other OpenSER registered phones the caller gets stuck in music on hold and the forward is never made.

Any pointers?

Many thanks in advance.