(gdb) bt full
#0  0x0000003b7a808913 in pthread_mutex_trylock () from /lib64/libpthread.so.0
No symbol table info available.
#1  0x00002aaabe55abb9 in ast_mutex_trylock (pmutex=0xe9) at /usr/src/asterisk-1.4.26/include/asterisk/lock.h:763
No locals.
#2  0x00002aaabe55aaf3 in local_queue_frame (p=0x1bae310, isoutbound=0, f=0x459a4530, us=0x1c6c6e0, us_locked=1) at chan_local.c:184
        other = (struct ast_channel *) 0x21
#3  0x00002aaabe55b2ff in local_indicate (ast=0x1c6c6e0, condition=18, data=0x0, datalen=0) at chan_local.c:385
        p = (struct local_pvt *) 0x1bae310
        res = 0
        f = {frametype = AST_FRAME_CONTROL, subclass = 18, datalen = 0, samples = 0, mallocd = 0, mallocd_hdr_len = 0, offset = 0, src = 0x0, data = 0x0, delivery = {tv_sec = 0, tv_usec = 0}, frame_list = {next = 0x0}, flags = 0, ts = 0, len = 0, seqno = 0}
        isoutbound = 0
#4  0x00000000004420d7 in ast_indicate_data (chan=0x1c6c6e0, _condition=18, data=0x0, datalen=0) at channel.c:2575
        condition = AST_CONTROL_VIDUPDATE
        ts = (const struct tone_zone_sound *) 0x0
        res = -1
        __PRETTY_FUNCTION__ = "ast_indicate_data"
#5  0x0000000000441fbb in ast_indicate (chan=0x1c6c6e0, condition=18) at channel.c:2520
No locals.
#6  0x00002aaab9ca4593 in process_incoming (member=0x1f1dea0, conf=0x1c12030, f=0x2aaab4082ae0) at member.c:142
        req_id = 1
        silent_frame = 0
        src_member = (struct ast_conf_member *) 0x2aaad008a570
#7  0x00002aaab9ca577e in member_exec (chan=0x2aaac4041620, data=0x459a69b0) at member.c:730
        conf = (struct ast_conference *) 0x1c12030
        member = (struct ast_conf_member *) 0x1f1dea0
        f = (struct ast_frame *) 0x2aaab4082ae0
        left = 40
        res = 0
        base = {tv_sec = 1263844161, tv_usec = 650938}
        curr = {tv_sec = 4334045552, tv_usec = 0}
        __PRETTY_FUNCTION__ = "member_exec"
#8  0x00002aaab9c9f4eb in app_conference_main (chan=0x2aaac4041620, data=0x459a69b0) at app_conference.c:67
        res = 0
        u = (struct ast_module_user *) 0x1ca42e0
#9  0x0000000000481f0c in pbx_exec (c=0x2aaac4041620, app=0x1b674b0, data=0x459a69b0) at pbx.c:536
        res = 0
        saved_c_appl = 0x0
        saved_c_data = 0x0
#10 0x0000000000485747 in pbx_extension_helper (c=0x2aaac4041620, con=0x0, context=0x2aaac4041870 "acd_conference_record", exten=0x2aaac40418c0 "60596", priority=5, label=0x0, callerid=0x2aaac4062540 "+19513231612", action=E_SPAWN) at pbx.c:1863
        e = (struct ast_exten *) 0x1e82f60
        app = (struct ast_app *) 0x1b674b0
        res = 1108336640
        q = {incstack = {0x0 <repeats 128 times>}, stacklen = 0, status = 5, swo = 0x0, data = 0x0, foundcontext = 0x2aaac4041870 "acd_conference_record"}
        passdata = "60596", '\0' <repeats 8186 times>
        matching_action = 0
        __PRETTY_FUNCTION__ = "pbx_extension_helper"
#11 0x00000000004867b7 in ast_spawn_extension (c=0x2aaac4041620, context=0x2aaac4041870 "acd_conference_record", exten=0x2aaac40418c0 "60596", priority=5, callerid=0x2aaac4062540 "+19513231612") at pbx.c:2283
No locals.
#12 0x0000000000486c2f in __ast_pbx_run (c=0x2aaac4041620) at pbx.c:2373
        dst_exten = "@\221\232E\000\000\000\000gc\200z;", '\0' <repeats 27 times                                                                                                                                                                                               2E", '\0' <repeats 16 times>, "\004\000\000\000P\220\232E", '\0' <repeats 36 tim                                                                                                                                                                                               ats 11 times>
        pos = 0
        digit = 0
        found = 1
        res = 0
        autoloopflag = 0
        error = 0
        emc = 0x0
        __PRETTY_FUNCTION__ = "__ast_pbx_run"
#13 0x0000000000487c7e in pbx_thread (data=0x2aaac4041620) at pbx.c:2599
        c = (struct ast_channel *) 0x2aaac4041620
#14 0x00000000004ca736 in dummy_start (data=0x2aaac40cc910) at utils.c:856
        __cancel_buf = {__cancel_jmp_buf = {{__cancel_jmp_buf = {0, -19634138552
        __cancel_routine = (void (*)(void *)) 0x424348 <ast_unregister_thread>
        __cancel_arg = (void *) 0x459a9940
        not_first_call = 0
        ret = (void *) 0x3b7a34c890
        a = {start_routine = 0x487c61 <pbx_thread>, data = 0x2aaac4041620, name
#15 0x0000003b7a806367 in start_thread () from /lib64/libpthread.so.0
No symbol table info available.
#16 0x0000003b7a0d309d in clone () from /lib64/libc.so.6