PHP apparently crashes under these contidions:
1. Use of serialize() on the $_SESSION variable
-AND-
2. $_SESSION contains an object
-AND-
3. object's class is not defined within the context of the serialize() call

Please contact me for gdb backtrace, php.ini, or other information if you cannot reproduce the problem with the script below.

Code that breaks:
<?php

	if( isset($_GET['serialize']) )
	{
		session_start();
		$serialized = serialize($_SESSION); // Causes seg fault
		print "Did not crash";
	}
	else
	{
		session_start();
		class Simple {}
		$_SESSION['simpleObj'] = new Simple();
		print '<a href="' . $_SERVER['PHP_SELF'] . '?serialize">serialize</a>';
	}
	
?>

Apache 1.3.27 error log:
[Fri Apr 18 14:04:05 2003] [notice] child pid 15705 exit signal Segmentation fault (11)
[Fri Apr 18 14:04:05 2003] [notice] child pid 15697 exit signal Segmentation fault (11)
[Fri Apr 18 14:04:05 2003] [notice] child pid 15693 exit signal Segmentation fault (11)