My ITSP has requested that the account username be send in the INVITE for each outgoing call for authentication purposes. I thought I had setup the trunk correctly as the REGISTER succeeds (Status 200) but when I try to make a call I get 400 Bad Request.
When I look at the INVITE request in the SIP from field it has '40@localhost'.
What the ITSP wants is username@your_pbx_IP address.
How can I configure this.
Thanks,
George