the problem is that the odbc_autocommit function has an option to be sent 
only with the connection id parameter, and in that case it should return us
the status of the autocommit (0 or 1).
in this short script when sent with no optional parameter the function produces "core dump".

<?php
$id = odbc_connect("zendtest", "db2inst1", "********");
$status = odbc_autocommit($id);//***this function crashe the system if send with no second parameter.***
?>