TEST SCRIPT:
<?
class xyz {
        var $x = array('a' => 'df', 'b' => 'dd', 'c' => 'fd');
}
$arr = get_class_vars('xyz');
while(list($key,$val) = each($arr)) print "Properties $key has value : $val\n";
?>

CONFIG LINE:
 './configure' '--with-mysql=/usr/local/mysql' '--enable-track-vars' '--without-gd' '--with-xml' '--without-ldap' '--without-imap'

Sorry, I couldn't get a gdb backtrace because my php wasn't compiled with the debug stuff turned on.  I suspect that you'd be able to reproduce this easily though.  Let me know if you need any more information from me.