(gdb) bt full
#0  0x0018b7a2 in _dl_sysinfo_int80 () from /lib/ld-linux.so.2
No symbol table info available.
#1  0x001cb7f5 in raise () from /lib/tls/libc.so.6
No symbol table info available.
#2  0x001cd199 in abort () from /lib/tls/libc.so.6
No symbol table info available.
#3  0x001ff4ea in __libc_message () from /lib/tls/libc.so.6
No symbol table info available.
#4  0x0020664c in _int_malloc () from /lib/tls/libc.so.6
No symbol table info available.
#5  0x002080b1 in malloc () from /lib/tls/libc.so.6
No symbol table info available.
#6  0x0022a11c in opendir () from /lib/tls/libc.so.6
No symbol table info available.
#7  0x0638a254 in __has_voicemail (context=0x639e598 "default", mailbox=0x766a220 "706", folder=0x639ef3e "INBOX", shortcircuit=0)
    at app_voicemail.c:2237
        dir = (DIR *) 0x0
        de = (struct dirent *) 0x0
        fn = "/var/spool/asterisk/voicemail/default/706/INBOX", '\0' <repeats 208 times>
        ret = 0
#8  0x0638a6b8 in inboxcount (mailbox=0x92494cc "706", newmsgs=0x766a378, oldmsgs=0x766a374) at app_voicemail.c:2313
        tmp = "706", '\0' <repeats 225 times>, "\027=1\000(£f\a\212³\v\b<£f\a\000\000\000\000(£f\aïx\005\b"
        context = 0x639e598 "default"
#9  0x0808a0cf in ast_app_inboxcount (mailbox=0x92494cc "706", newmsgs=0x766a378, oldmsgs=0x766a374) at app.c:189
        warned = 0
#10 0x04f37a97 in sip_send_mwi_to_peer (peer=0x9248f88) at chan_sip.c:14196
        p = (struct sip_pvt *) 0x4f02846
        newmsgs = 0
        oldmsgs = 0
#11 0x04f38271 in do_monitor (data=0x0) at chan_sip.c:14364
        res = 0
        sip = (struct sip_pvt *) 0x0
        peer = (struct sip_peer *) 0x9248f88
        t = 1150927386
        fastrestart = 1
        lastpeernum = 2
        curpeernum = 3
        reloading = 0
        __PRETTY_FUNCTION__ = "do_monitor"
#12 0x080bac81 in dummy_start (data=0x924b048) at utils.c:536
        _buffer = {__routine = 0x80a664d <ast_unregister_thread>, __arg = 0x766abb0, __canceltype = 0, __prev = 0x0}
        ret = (void *) 0x0
        a = {start_routine = 0x4f37ceb <do_monitor>, data = 0x0,
  name = 0x924b058 "do_monitor", ' ' <repeats 11 times>, "started at [14395] chan_sip.c restart_monitor()"}
#13 0x00312371 in start_thread () from /lib/tls/libpthread.so.0
No symbol table info available.
#14 0x0026b9be in clone () from /lib/tls/libc.so.6
No symbol table info available.