TIPcon1 client v1.5.1 provides in a SIP REGISTER request Contact URI as per configuration e.g. Contact: <sip:tip1@47.11.71.243>
But, when originating a call with an INVITE request, TIPcon1 client provides Contact URI that does not match the one from the active registration e.g. Contact: <sip:user@47.11.71.243>
Username "user" seem to be hard-coded in the TIPcon1 v1.5.1.
This causes call originations to fail in most of the SIP environments.