Conditional content with WPLANG.

Hi I am trying to get a site multilingual & everything else is set, I am using .po & .mo for localization & have achieved the language switching by a single href=?lang=en_us & likewise.

Now the issue is everything else is translated, but not the navigation menus, so I tried getting another approach, i made 2 menus for it, one in english & one in other language i need, now i simply need to know how to show differnent menus if wplang is changed.

Something like this :

<?php
if(defined(‘WPLANG’) == ‘en-US’) {
echo ‘YES’;
}
else if(defined(‘WPLANG’) != ‘en-US’) {
echo ‘no’;
}
?>

How can I achieve this ? Any quick ideas ? Thanks very much in advance! Cheers!