Event firing twice (again... I know...)

Event firing twice (again... I know...)

I notice that there has been talk about peoples Jquery functions firing twice.
But none of the answers to their problems seem to solve mine..

Can anyone tell me why this event i fired twice:
(When I click any one of my links with the class "popweb_jquery_tran", the event is being fired twice)

$(document).ready( function() {
$('.popweb_jquery_trans').unbind("click").click( function(){

     $('#JQ_content_box, #JQ_footer_sublinks').animate({
    opacity: 0
  }, 500, function() {
  
});
return false;
});
});


There are a bunch of links with the class "popweb_jquery_trans" in my html (php). Because I want any of these links to fire this event.
What am I doing wrong?