(gdb) bt
#0  0xb7fbbce4 in pthread_mutex_lock () from /lib/tls/libpthread.so.0
#1  0xb64c9d0a in sip_fixup (oldchan=0xaeeb3970, newchan=0xaeeb3970) at chan_sip.c:1862
#2  0x08060679 in ast_do_masquerade (original=0xaeeb3970) at channel.c:2370
#3  0x0805d207 in ast_read (chan=0xaeeb3970) at channel.c:1205
#4  0x080616b2 in ast_channel_bridge (c0=0xaeeb3970, c1=0x840be50, config=0xb44ad230,
    fo=0xb44ad1e8, rc=0xb44ad1e4) at channel.c:2650
#5  0xb758f6f5 in ast_bridge_call (chan=0xaeeb3970, peer=0x840be50, config=0xb44ad230)
    at res_features.c:348
#6  0xb60907e0 in try_calling (qe=0xb44ad520, options=0xb44ad669 "r", announceoverride=0x0,
    url=0x0, go_on=0xb44ad644) at app_queue.c:1218
#7  0xb6092099 in queue_exec (chan=0xaeeb3970, data=0xb44adb6b) at app_queue.c:1655
#8  0x080738de in pbx_exec (c=0xaeeb3970, app=0xb5f040c8, data=0xb44adb6b, newstack=1)
    at pbx.c:469
#9  0xb7598802 in handle_exec (chan=0xaeeb3970, agi=0xb44ae3c0, argc=3, argv=0xb44ad920)
    at res_agi.c:828
#10 0xb759970a in agi_handle_command (chan=0xaeeb3970, agi=0xb44ae3c0, buf=0xb44adb60 "EXEC")
    at res_agi.c:1452
#11 0xb7599aad in run_agi (chan=0xaeeb3970, request=0xb44ae3f0 "ExtensionDial.agi",
    agi=0xb44ae3c0, pid=17589, dead=0) at res_agi.c:1532
#12 0xb759a16d in agi_exec_full (chan=0xaeeb3970, data=0xb44b0f70, enhanced=0, dead=0)
    at res_agi.c:1671
#13 0xb759a2c9 in agi_exec (chan=0xaeeb3970, data=0xb44b0f70) at res_agi.c:1684
#14 0x080738de in pbx_exec (c=0xaeeb3970, app=0x80fdd30, data=0xb44b0f70, newstack=1)
    at pbx.c:469
#15 0x08075e17 in pbx_extension_helper (c=0xaeeb3970, context=0xaeeb3ac8 "macro-extdial",
    exten=0xaeeb3bbc "s", priority=3, callerid=0xaee54450 "<2326>", action=1) at pbx.c:1277
#16 0x08076dce in ast_spawn_extension (c=0xaeeb3970, context=0xaeeb3ac8 "macro-extdial",
    exten=0xaeeb3bbc "s", priority=3, callerid=0xaee54450 "<2326>") at pbx.c:1758
#17 0xb609915e in macro_exec (chan=0xaeeb3970, data=0xb44b57e0) at app_macro.c:141
#18 0x080738de in pbx_exec (c=0xaeeb3970, app=0xb5f03c60, data=0xb44b57e0, newstack=1)
    at pbx.c:469
#19 0x08075e17 in pbx_extension_helper (c=0xaeeb3970, context=0xaeeb3ac8 "macro-extdial",
    exten=0xaeeb3bbc "s", priority=1, callerid=0xaee54450 "<2326>", action=1) at pbx.c:1277
#20 0x08076dce in ast_spawn_extension (c=0xaeeb3970, context=0xaeeb3ac8 "macro-extdial",
    exten=0xaeeb3bbc "s", priority=1, callerid=0xaee54450 "<2326>") at pbx.c:1758
#21 0x080771b7 in ast_pbx_run (c=0xaeeb3970) at pbx.c:1817
#22 0x08077c34 in pbx_thread (data=0xaeeb3970) at pbx.c:1981
#23 0xb7fb998c in start_thread () from /lib/tls/libpthread.so.0
#24 0xb7eaa7da in clone () from /lib/tls/libc.so.6
(gdb)