Hi, fix_nated_contact() and fix_nated_register() don't appear to change the Contact at all when the source of the message is TCP. I log the value of $ct before and after, and there is no change. Kamailio tries to send to the original private IP, as well. The transport=TCP attribute is present in the Contact header in all cases. Is there something I should know about how to make these functions work with TCP? If not, what's the solution? Thank you, -- Alex -- Sent from my mobile, and thus lacking in the refinement one might expect from a fully fledged keyboard. Alex Balashov - Principal Evariste Systems LLC 235 E Ponce de Leon Ave Suite 106 Decatur, GA 30030 United States Tel: +1-678-954-0670 Web: http://www.evaristesys.com/, http://www.alexbalashov.com