I think that PHP+IMAP+MySQL application causes Segmentation fault (11)
Some other php scripts whitch access MySQL tables works fine.

php.ini is exactly php.ini-dist

php configured:
./configure --with-apxs --eable-memory-limit --enable-track-vars --with-mysql --with-imap

Backtrace report:

(gdb) run -X -f /etc/httpd/conf/httpd.conf
Starting program: /usr/local/apache/bin/httpd -X -f /etc/httpd/conf/httpd.conf

Program received signal SIGSEGV, Segmentation fault.
0x401976a8 in main_arena ()
(gdb) bt
#0  0x401976a8 in main_arena ()
#1  0x40337a17 in search (base=0x8122a48 "`v\031@`v\031@", basec=0, 
    pat=0x4040ba24 "x?\035", patc=134976780) at misc.c:260
#2  0x402b0d6e in php_if_imap_body (ht=135610524, return_value=0x4040ba24, 
    this_ptr=0x810d484, return_value_used=135174952) at php_imap.c:1114
#3  0x402900fe in zend_if_get_class_methods (ht=134976780, 
    return_value=0x4040ba24, this_ptr=0x40420e04, return_value_used=7)
    at zend_builtin_functions.c:586
#4  0x4028ee8f in zend_if_strncmp (ht=1078070788, return_value=0x0, 
    this_ptr=0x0, return_value_used=7) at zend_builtin_functions.c:256
#5  0x4028fda9 in zend_if_get_class_vars (ht=7, return_value=0x4040ba24, 
    this_ptr=0x402b259c, return_value_used=1076569500)
    at zend_builtin_functions.c:516
#6  0x402b27a4 in php_if_imap_listscan (ht=1, return_value=0x814a93c, 
    this_ptr=0x0, return_value_used=0) at php_imap.c:1449
#7  0x4027f6d6 in execute (op_array=0x811efb0) at ./zend_execute.c:1974
#8  0x4027f927 in execute (op_array=0x810bd80) at ./zend_execute.c:2024
#9  0x4027f927 in execute (op_array=0x813862c) at ./zend_execute.c:2024
#10 0x40281995 in _get_zval_ptr_ptr (node=0x814b764, Ts=0x4040ba24)
    at ./zend_execute.c:165
#11 0x4028be20 in zend_load_extension (path=0x8 <Address 0x8 out of bounds>)
    at zend_extensions.c:44
#12 0x4029b1d2 in yyunput (c=-1073742892, yy_bp=0x4040ba24 "x?\035")
    at configuration-scanner.c:1301
#13 0x40297e09 in php_error_cb (type=135289124, error_filename=0x0, 
    error_lineno=135289124, format=0x8105924 "?X\020\b?H\020\b??\n\b", 
    orig_args=0x403887fa) at main.c:384
#14 0x402986cb in php_module_startup (sf=0x8105924) at main.c:824
#15 0x402986fc in php_module_startup (sf=0x8105924) at main.c:842
#16 0x8054383 in ap_invoke_handler ()
#17 0x80678b9 in process_request_internal ()
#18 0x806791c in ap_process_request ()
#19 0x805f1be in child_main ()
#20 0x805f34c in make_child ()
#21 0x805f4a9 in startup_children ()
#22 0x805fad6 in standalone_main ()
#23 0x8060263 in main ()
#24 0x400c6cb3 in __libc_start_main (main=0x805ff1c <main>, argc=4, 
    argv=0xbffffd94, init=0x804e910 <_init>, fini=0x809423c <_fini>, 
    rtld_fini=0x4000a350 <_dl_fini>, stack_end=0xbffffd8c)
    at ../sysdeps/generic/libc-start.c:78