Additional null check on _drop

Hi,

I have an app where droppable items are added dynamically via ajax. My droppable item's html is returned from the server, and then I register them as droppable via jQuery UI once they are added to the DOM.

Sometimes when these items are dropped in Firefox 3.6.9 (especially when dragging upwards and then dropping I get:

"inst is null" on line 1736. (the code is in "ui.droppable")

I'm using jQuery UI 1.8, but I tried 1.8.4 and had the same issue.

I added the following check for null "inst!=null &&", under the comment "// jhk".

Once I added this, all is well, and drop is working properly.

_drop: function(event,custom) {

		var draggable = custom || $.ui.ddmanager.current;
		if (!draggable || (draggable.currentItem || draggable.element)[0] == this.element[0]) return false; // Bail if draggable and droppable are same element
        
		var childrenIntersection = false;
		this.element.find(":data(droppable)").not(".ui-draggable-dragging").each(function() {
			var inst = $.data(this, 'droppable');
			if(
                // jhk - added "inst!=null &&"
                inst!=null &&
				inst.options.greedy
				&& !inst.options.disabled
				&& inst.options.scope == draggable.options.scope
				&& inst.accept.call(inst.element[0], (draggable.currentItem || draggable.element))
				&& $.ui.intersect(draggable, $.extend(inst, { offset: inst.element.offset() }), inst.options.tolerance)
			) { childrenIntersection = true; return false; }
		});

I have not tried other browsers.

Thanks,

Jon