#0  0x401ec60e in transmit_register (r=0x8128b48, cmd=0x401fd637 "REGISTER",
    auth=0xbedfd7b4 "Digest username=\"89437\", realm=\"fwd.pulver.com\", algorithm=\"MD5\", uri=\"sip:fwd.pulver.com\", nonce=\"401e86a452f0267d0b89bd466c9465f451e69d2f\", response=\"86f0f9186b276bc101fbc89f4ed86bcd\"", authheader=0x401fe74e "Authorization") at chan_sip.c:3216
3216                    snprintf(from, sizeof(from), "<sip:%s@%s>;tag=as%08x", r->username, r->hostname, p->tag);
(gdb) bt
#0  0x401ec60e in transmit_register (r=0x8128b48, cmd=0x401fd637 "REGISTER",
    auth=0xbedfd7b4 "Digest username=\"89437\", realm=\"fwd.pulver.com\", algorithm=\"MD5\", uri=\"sip:fwd.pulver.com\", nonce=\"401e86a452f0267d0b89bd466c9465f451e69d2f\", response=\"86f0f9186b276bc101fbc89f4ed86bcd\"", authheader=0x401fe74e "Authorization") at chan_sip.c:3216
#1  0x401f225b in do_register_auth (p=0x81261c8, req=0xbedff284, header=0x401fe75c "WWW-Authenticate", respheader=0x401fe74e "Authorization") at chan_sip.c:4619
#2  0x401f37e5 in handle_response (p=0x81261c8, resp=401, rest=0xbedff4a4 "Unauthorized", req=0xbedff284, ignore=1) at chan_sip.c:4981
#3  0x401f6904 in handle_request (p=0x81261c8, req=0xbedff284, sin=0xbedff274, recount=0xbedff26c) at chan_sip.c:5578
#4  0x401f6bf3 in sipsock_read (id=0x81115b8, fd=13, events=1, ignore=0x0) at chan_sip.c:5631
#5  0x080517f0 in ast_io_wait (ioc=0x80e7500, howlong=187) at io.c:267
#6  0x401f70bb in do_monitor (data=0x0) at chan_sip.c:5736
#7  0x400230ba in pthread_start_thread () from /lib/libpthread.so.0