This does not mean that it stops working. The fact is that it binds handlers clickonly to those elements that exist at startup (when the page loads).
You can put a .delegate()handler on <div>which dynamic ones are loaded.
$('#mydiv').delegate('a.selected_class','click',function(e){
alert('alert');
e.preventDefault();
});
#mydiv, click , , , a.selected_class.
.live() , , .