Another crahs with backtrace:

GNU gdb 6.8-debian Copyright (C) 2008 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later http://gnu.org/licenses/gpl.html This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "i486-linux-gnu"... Reading symbols from /lib/i686/cmov/libcrypt.so.1...Reading symbols from /usr/lib/debug/lib/i686/cmov/libcrypt-2.9.so...done. done. Loaded symbols for /lib/i686/cmov/libcrypt.so.1 Reading symbols from /lib/libpam.so.0...done. Loaded symbols for /lib/libpam.so.0 Reading symbols from /lib/i686/cmov/libdl.so.2...Reading symbols from /usr/lib/debug/lib/i686/cmov/libdl-2.9.so...done. done. Loaded symbols for /lib/i686/cmov/libdl.so.2 Reading symbols from /lib/i686/cmov/libc.so.6...Reading symbols from /usr/lib/debug/lib/i686/cmov/libc-2.9.so...done. done. Loaded symbols for /lib/i686/cmov/libc.so.6 Reading symbols from /lib/ld-linux.so.2...Reading symbols from /usr/lib/debug/lib/ld-2.9.so...done. done. Loaded symbols for /lib/ld-linux.so.2 Reading symbols from /lib/i686/cmov/libnss_compat.so.2...Reading symbols from /usr/lib/debug/lib/i686/cmov/libnss_compat-2.9.so...done. done. Loaded symbols for /lib/i686/cmov/libnss_compat.so.2 Reading symbols from /lib/i686/cmov/libnsl.so.1...Reading symbols from /usr/lib/debug/lib/i686/cmov/libnsl-2.9.so...done. done. Loaded symbols for /lib/i686/cmov/libnsl.so.1 Reading symbols from /lib/i686/cmov/libnss_nis.so.2...Reading symbols from /usr/lib/debug/lib/i686/cmov/libnss_nis-2.9.so...done. done. Loaded symbols for /lib/i686/cmov/libnss_nis.so.2 Reading symbols from /lib/i686/cmov/libnss_files.so.2...Reading symbols from /usr/lib/debug/lib/i686/cmov/libnss_files-2.9.so...done. done. Loaded symbols for /lib/i686/cmov/libnss_files.so.2 Reading symbols from /lib/libgcc_s.so.1...done. Loaded symbols for /lib/libgcc_s.so.1 Core was generated by `dovecot-auth'. Program terminated with signal 6, Aborted. [New process 7692] #0 0xb8071424 in __kernel_vsyscall () #0 0xb8071424 in __kernel_vsyscall () No symbol table info available. #1 0xb7eee680 in *__GI_raise (sig=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64 resultvar = <value optimized out> pid = -1207832588 selftid = 7692 #2 0xb7ef1d68 in *__GI_abort () at abort.c:88 act = {__sigaction_handler = {sa_handler = 0x8f90618, sa_sigaction = 0x8f90618}, sa_mask = {__val = {3220762632, 134653482, 3087132384, 0, 3220762752, 3220762740, 512, 0, 0, 3220762816, 3087595120, 134536646, 541, 0, 0, 0, 1, 134703806, 512, 1, 3220762740, 150537720, 69, 3220762868, 3220762712, 134655078, 150538293, 3220762740, 3220762744, 542, 150537752, 3086574819}}, sa_flags = 542, sa_restorer = 0x807af69 } sigs = {__val = {32, 0 }} #3 0x0806c7a5 in default_fatal_finish (type=<value optimized out>, status=0) at failures.c:160 backtrace = 0x8f901e8 "dovecot-auth [0x806c791] -> dovecot-auth [0x806c812] -> dovecot-auth [0x806c199] -> dovecot-auth [0x8056bd4] -> dovecot-auth(auth_request_set_username+0xaf) [0x8056c8f] -> dovecot-auth [0x805cdf2] -> "... #4 0x0806c812 in i_internal_fatal_handler (type=LOG_TYPE_PANIC, status=0, fmt=0x807bd34 "file %s: line %d (%s): assertion failed: (%s)", args=0xbff8f154 "\207�\a\bg\003") at failures.c:440 No locals. #5 0x0806c199 in i_panic ( format=0x807bd34 "file %s: line %d (%s): assertion failed: (%s)") at failures.c:207 No locals. #6 0x08056bd4 in auth_request_set_login_username (request=0x9060148, username=0x8f901b0 "", error_r=0xbff8f1d8) at auth-request.c:871 __PRETTY_FUNCTION__ = "auth_request_set_login_username" #7 0x08056c8f in auth_request_set_username (request=0x9060148, username=0x8f9018a "masteruser", error_r=0xbff8f1d8) at auth-request.c:859 login_username = 0x8f901b0 "" #8 0x0805cdf2 in mech_plain_auth_continue (request=0x9060148, data=0x8f90188 "", data_size=21) at mech-plain.c:47 authid = 0x8f90188 "" authenid = 0x8f90189 "*masteruser" error = <value optimized out> pass = 0x8f901a0 "xxxxxxxx" i = <value optimized out> count = <value optimized out> #9 0x0805846c in auth_request_handler_auth_begin (handler=0x90dddd0, args=0x90dcf70 "4877\tPLAIN\tservice=imap\tsecured\tlip=127.0.0.1\trip=127.0.0.1\tlport=993\trport=43362\tresp=ACptYXN0ZXJ1c2VyAFppR2FHaW5a") at auth-request-handler.c:385 mech = <value optimized out> request = (struct auth_request *) 0x9060148 list = (const char * const *) 0x8f900c8 name = 0x8f90168 "\210\001�\b\025" arg = 0x8f90087 "ACptYXN0ZXJ1c2VyAFppR2FHaW5a" initial_resp = <value optimized out> initial_resp_len = 6 id = 4877 buf = (buffer_t *) 0x8f90168 #10 0x080539ce in auth_client_input (conn=0x8f9add8) at auth-client-connection.c:174 _data_stack_cur_id = 3 line = 0x90dcf6b "AUTH\t4877\tPLAIN\tservice=imap\tsecured\tlip=127.0.0.1\trip=127.0.0.1\tlport=993\trport=43362\tresp=ACptYXN0ZXJ1c2VyAFppR2FHaW5a" ret = 2 #11 0x08070430 in io_loop_handler_run (ioloop=0x8f981a8) at ioloop-epoll.c:208 ctx = (struct ioloop_handler_context *) 0x8f9ab58 event = (const struct epoll_event *) 0x90d4a20 list = (struct io_list *) 0x8f9afa8 io = (struct io_file *) 0x8f9af80 tv = {tv_sec = 1, tv_usec = 290883} t_id = 2 msecs = <value optimized out> ret = 1 i = 0 j = 0 call = <value optimized out> #12 0x0806f8a0 in io_loop_run (ioloop=0x8f981a8) at ioloop.c:338 No locals. #13 0x0805c5a4 in main (argc=) at main.c:347 foreground = false (gdb) quit

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