config.nice
'./configure' \
'--with-apxs=/www/bin/apxs' \
'--with-mysql' \
'--with-pgsql=/usr/local/pgsql' \
'--without-pear' \
'--with-gd' \
'--enable-wddx' \
'--with-xmlrpc' \
'--with-curl' \
'--enable-debug' \
"$@"

backtrace:

#0  0x40540d89 in execute (op_array=0x81bb53c) at ./zend_execute.c:1815
#1  0x4053fe02 in execute (op_array=0x8237a40) at ./zend_execute.c:1630
#2  0x4053fe02 in execute (op_array=0x81947cc) at ./zend_execute.c:1630
#3  0x4054e574 in zend_execute_scripts (type=8, retval=0x0, file_count=3) at zend.c:814
#4  0x4055bfa1 in php_execute_script (primary_file=0xbffff600) at main.c:1307
#5  0x40558082 in apache_php_module_main (r=0x8186b24, display_source_mode=0) at sapi_apache.c:90
#6  0x40558b65 in send_php (r=0x8186b24, display_source_mode=0, filename=0x0) at mod_php4.c:575
#7  0x40558bba in send_parsed_php (r=0x8186b24) at mod_php4.c:590
#8  0x808bded in ap_invoke_handler ()
#9  0x80a0fab in process_request_internal ()
#10 0x80a100c in ap_process_request ()
#11 0x8098051 in child_main ()
#12 0x8098220 in make_child ()
#13 0x8098390 in startup_children ()
#14 0x8098a09 in standalone_main ()
#15 0x80992a3 in main ()
#16 0x4016db65 in __libc_start_main (main=0x8098ee0 <main>, argc=2, ubp_av=0xbffffb14, init=0x8054a30 <_init>, 
    fini=0x80d132c <_fini>, rtld_fini=0x4000df24 <_dl_fini>, stack_end=0xbffffb0c) at ../sysdeps/generic/libc-start.c:111

Only happens under POST and then a Header("location: ...") as far as i cant tell