Someone

$error = TRUE;
if (SQL_LAYER == "mysql" || SQL_LAYER == "mysql4")
{
    echo "Check 1<br/>";
    $sql_error = $db->sql_error($result);
    if ($sql_error["code"] == 1114)
    {
        $result = $db->sql_query('SHOW TABLE STATUS LIKE "'.SESSIONS_TABLE.'"');
        $row = $db->sql_fetchrow($result);
        if ($row["Type"] == "HEAP")
        {
            echo "check 2<br/>";
            if ($row["Rows"] > 2500)
            {
                echo "check 3a<br/>";
                $delete_order = (SQL_LAYER=="mysql4") ? " ORDER BY session_time ASC" : "";
                $db->sql_query("DELETE QUICK FROM ".SESSIONS_TABLE."$delete_order LIMIT 50");
            }
            else
            {
                echo "check3b<br/>";
                $db->sql_query("ALTER TABLE ".SESSIONS_TABLE." MAX_ROWS=".($row["Rows"]+50));
            }
            if ($db->sql_query($sql))
            {
                echo "final check<br/>;
                $error = FALSE;
            }
        }
    }
}
if ($error)
{
    message_die(CRITICAL_ERROR, "Error creating new session", "", __LINE__, __FILE__, $sql);
}