jquery draggable with safari 4

Question

$(".droppable").droppable({ drop: function(event, ui) {

                var fileName = $(ui.draggable).attr("src").match(/[\/|\\]([^\\\/]+)$/); // get filename.

                var url = $("#hurl").val();
                if ( $(ui.draggable).attr('name') == "template")
                    url = $("#turl").val();

                var obj = $(ui.draggable).clone().attr("src",url+fileName[1]).css("width","345px").css("height","215px");
                $(this).empty();
                obj.draggable({
                     distance: 100,
                     helper: 'clone',
                     opacity : 0.35,
                     revert: 'valid',
                        stop: function(event, ui) {
                            $(this).remove(); 
                        }

                    } //obj.draggable 
                );
                $(this).append(obj);
            },//drop:

         accept : ".draggable_template"  
         }

       );

above code worked for IE7, IE6, firefox 3, chrome, opera 10beta, but not safari 4. the problem is in

stop: function(event, ui) { 
    $(this).remove(); 
}

In safari 4, this piece of code is not be called.