Description:
------------
The following source gives segfault on CentOS 4.3 64-Bit and  PHP 5.2.2.
Don't be scared, this regular expression is real parser for my templates-engine, and it works with other operation systems.
The result depends on Subject, so with '$var' it works well, but if '$var[anything]' then crashes.

Reproduce code:
---------------
<?php
echo 'proof of compilation'."\n";
preg_replace(
    '~(([\'"]).*?(?<!\\\\)\2|\w*\s*\(((?:(?R)|.)*?)\)'
    .'|[\$#]\w+#?(?:\\[(?:(?R)|((?:[^\\]\'"]*(?:([\'"]).*?(?<!\\\\)\5)?)*))*?\\]|\.[\$#]?\w+#?|->\s*[\$#]?\w+(?:\(((?:(?R)|.)*?)\))?)*'
    .'|-?\d+|(?<=^|[\s\)\:\.=+\-<>])(?:\w+)(?=$|[\s\|\.\:\(=+\-<>]))(\s+(?:is(?:\s+not)?\s+(?:odd|div|even)\s+by\s+-?\d+|is(?:\s+not)?\s+(?:odd|even)))?((?:\|@?\w+(?:\\:(?:'.'\w*\(((?:(?R)|.)*?)\)|[\$#]\w+#?(?:\\[(?:(?R)|((?:[^\\]\'"]*(?:([\'"]).*?(?<!\\\\)\11)?)*))*?\\]|\.[\$#]?\w+#?)*|[^\'"\:]*(?:[^\'"\:]*([\'"]).*?(?<!\\\\)\12[^\'"\:]*)*'.'))*)*)'
    .'|((?<=\s|\))(?:is\s+not|is|not\s+eq|eq|neq?|gt|lt|gt?e|ge|lt?e|mod)(?=\s|\()|(?:not\s+))'
    .'~si','any replacement','$var[index]');

Expected result:
----------------
"any replacement"

Actual result:
--------------
[root@72 _test]# php -q bug.php
proof of compilation
Segmentation fault