<HTML>
  <HEAD><TITLE>list bug</TITLE></HEAD>
  <BODY BGCOLOR=White>
    <TABLE BORDER=1>
    <?php
     $a = "Yes";
     $b = "no";
     if("x" == "y"){
       list($m,$n) = "";
     }
     print "<TR><TD>$a</TD><TD>$b</TD></TR>\n";
    ?>
    </TABLE>
  </BODY>
</HTML>

The above script when *repeatedly* called gives inconsistent results. Even though the list() function is not actually called it causes the problem (and yes I know its bad syntax) so I presume this is a bug with the parsing engine !

Included modules and settings do not seem to alter the behaviour.