--- ui.droppable.js	2007-12-07 03:22:24.000000000 -0800
+++ ui.droppable-overlap.js	2007-12-15 00:03:50.000000000 -0800
@@ -165,6 +165,10 @@
 		var l = oDrop.offset.left, r = l + oDrop.item.element.offsetWidth, 
 		    t = oDrop.offset.top,  b = t + oDrop.item.element.offsetHeight;
 		switch (toleranceMode) {
+			case 'overlap':
+				dao = $(oDrag.helper).offset();
+				dpo = oDrop.offset;
+				return ( dao.top == dpo.top && dao.left == dpo.left );
 			case 'fit':
 				return (   l < x1 && x2 < r
 					&& t < y1 && y2 < b);