[Serusers] REGISTER loops from specific location

Hi folks, I was experimenting with SER awhile back and am now revisiting it. I've just setup a SER installation using the latest debian packages on a server outside of our office firewall on a public IP address. From home, my laptop on a private IP behind a linksys router/firewall can login/register with my SER server fine. It can also login/register into my iptel.org account as well. Then when I get to the office, behind our firewall, I have problems. I can still login/register my iptel.org account from my laptop on a private IP behind the office firewall, but when I try to log into the SER server I setup it seems to go into a loop (see logs below). I'm using stunserver.org in all cases. I wonder about the line pre_auth(): Credentials with given realm not found but then it works fine using the same login info from home. Also, when all this gives up my softphone says: Registration rejected. Response:Server could not be reached, or it did not respond. Any ideas appreciated. Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: SIP Request: Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: method: <REGISTER> Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: uri: <sip:sip.example.org> Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: version: <SIP/2.0> Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: parse_headers: flags=1 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: end of header reached, state=5 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: parse_headers: Via found, flags=1 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: parse_headers: this is the first vi a Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: After parse_msg... Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: preparing to run routing scripts... Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: DEBUG : is_maxfwd_present: searchin g for max_forwards header Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: parse_headers: flags=128 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: end of header reached, state=8 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: DEBUG: get_hdr_field: <To> [28]; ur i=[sip:markjr@sip.example.org] Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: DEBUG: to body [sip:markjr@sip.easy dns.org^M ] Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: get_hdr_field: cseq <CSeq>: <142240 54> <REGISTER> Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: DEBUG: get_hdr_body : content_lengt h=0 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: found end of header Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: DEBUG: is_maxfwd_present: max_forwa rds header not found! Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: end of header reached, state=8 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: DEBUG: get_hdr_field: <To> [28]; ur i=[sip:markjr@sip.example.org] Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: DEBUG: to body [sip:markjr@sip.easy dns.org^M ] Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: get_hdr_field: cseq <CSeq>: <142240 54> <REGISTER> Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: DEBUG: get_hdr_body : content_lengt h=0 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: found end of header Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: DEBUG: is_maxfwd_present: max_forwa rds header not found! Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: end of header reached, state=8 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: parse_headers: flags=256 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: find_first_route(): No Route header s found Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: loose_route(): There is no Route HF Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: check_self - checking if host==us: 15==9 && [sip.example.org] == [127.0.0.1] Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: check_self - checking if port 5060 matches port 5060 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: check_self - checking if host==us: 15==13 && [sip.example.org] == [66.207.199.42] Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: check_self - checking if port 5060 matches port 5060 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: DBUG: entering REGISTER branch Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: parse_headers: flags=4096 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: pre_auth(): Credentials with given realm not found Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: build_auth_hf(): 'WWW-Authenticate: Digest realm="sip.example.org", nonce="42cacdeb905244dcc9e7ebc71f60fb5aaa658faf"^M ' Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: parse_headers: flags=-1 Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: check_via_address(66.207.199.34, 19 2.168.1.18, 0) Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: DEBUG:destroy_avp_list: destroing l ist (nil) Jul 5 14:09:03 tmda /usr/sbin/ser[21028]: receive_msg: cleaning up