Odd extra elements in URL after form submission

[gjh42]

I have been rewriting the Orders Export mod and have an odd situation.
http://www.zen-cart.com/showthread.p...22#post1256922
I should have started this question here so as not to repeat myself.

When selecting an export range, two odd elements are added to the URL in the address bar. They vary seemingly at random in the numbers, but always look like ...&x=23&y=9.
For example:

http://localhost/zc151/my_admin/orders_export.php?from_oid=1&to_oid=99&x=38&y=6

I don't know what in the form submission would insert that, and would like to eliminate it.

    <div class="oidSetting"> <!-- Order ID setting inputs -->
      <h2><?php echo ORDERSEXPORT_PAGE_HEADING_OID; ?></h2>
      <?php echo zen_draw_form('oid_range', FILENAME_ORDERSEXPORT, '', 'get');
      echo '<div class="oidInput">' . OEX_FROM_OID_PRE . zen_draw_input_field('from_oid', $limits['orders_id'][0], 'size="10"') . '</div>';
      echo '<div class="oidInput">' . OEX_TO_OID_PRE . zen_draw_input_field('to_oid', $limits['orders_id'][1], 'size="10"') . '</div>';
      echo '<div class="oidSubmit">' . zen_image_submit('button_save.gif', IMAGE_SAVE) . '</div>';//form submit
      echo '</form>';?>
    </div>