[Freeswitch-users] How to set user in contact header on b-leg for external gateway?

Hi, Call comes over external gateway and pass to another external gateway via outbound proxy (no authentication nor registration), but on b-leg contact header is not as expected username from tag 'From:' of a-leg. a-leg works correct for inbound calls via external gateway: Contact: <sip:1001@1.2.3.4:5060;transport=udp> but b-leg (outbound calls) has header set to: Contact: <sip:auto_to_user@1.2.3.4:5060;transport=udp;gw=mygw> I tried to set empty value or comment this line of external gateway: <param name="extension" value="auto_to_user"/> but then call failed. How to set user in contact header on b-leg or/and what to export from dial plan to populate user in contact header on external gateway? Regards, Seudin