try this code... it works fine on php4cvs but crashes at around $i==4000 (on my pc).

<?php
$a=0;
for ($i=0; $i<30000; $i++) {eval('$a += 1;');print($a.'<br>');}
?>

it does not matter what i'm evaluing.... just increase $i.. and it will crash. (php3cvs DSO with versioning)