<form name="form" id="form" action='la misma pagina'>
<select name="jumpMenu" id="jumpMenu" onChange="MM_jumpMenu('parent',this,0)">
<option value = '1'>item1</option>
<option value = '2'>item2</option>
<option value = '3'>item3</option>
</select>
</form>
y en la misma pagina pondrías:
<php
$value = $_POST['jumpMenu'];
y ya tienes la variable ;)