I've added the environment variables to our FS startup script to enable debugging: export SOFIA_DEBUG=9 export NUA_DEBUG=9 export NTA_DEBUG=9 export TPORT_DEBUG=9 export TPORT_LOG=1 However, when I do a "load mod_sofia" from fs_cli, no debug output is produced indicating that FS sent the request, nor whether it's received the response from Erlang. Our Erlang code does log that the response was sent (and the text of that response), but FS is still hanging with the source code build of 1.0.4. I'm at a bit of a loss here. I really don't want to modify the FS source code, but it's starting to look like that's going to be the only option for debugging this problem. -- Mark Sobkow Senior Developer MarkeTel Multi-Line Dialing Systems LTD. 428 Victoria Ave Regina, SK S4N-0P6 Toll-Free: 800-289-8616-X533 Local: 306-359-6893-X533 Fax: 306-359-6879 Email: m.sobkow@marketelsystems.com Web: http://www.marketelsystems.com