Jquery ui selectable cannot load xml

Question

Hello all, I'm trying to load XML file after a selectable is clicked. Everything goes fine except it never executes any codes within

$('occupancy',theXML).each(function(i) { alert("never executes"); });

Can someone please advise me? Here is the rest of the code:

$("#selectable").selectable({
    selected: function(){    
        $(".ui-selected", this).each(function(){ 
             $oid = $(this).attr('name'); // everything here executes fine
        });
        $.get("occupancy/xmlInfoForm.php", { oid: $oid }, function(theXML) { 
             // chrome debug shows that it loads the right XML with right oid, but never executes the alert below
             $('occupancy',theXML).each(function(i) {  
                  alert(theXML) // this is the alert that never executes
             });
        });
    }   
});