Index: wp-admin/js/widgets.js
===================================================================
--- wp-admin/js/widgets.js	(revision 32453)
+++ wp-admin/js/widgets.js	(working copy)
@@ -135,6 +135,17 @@
 					// Prevents jumping when dragging a widget from an open sidebar to a closed sidebar below.
 					height = ui.item.hasClass('ui-draggable') ? $this.height() : 1 + $this.height();
 					$this.css( 'min-height', height + 'px' );
+				} else { 
+					var hashoverover;
+					$($wrap).mouseover(function() {
+						hashoverover = setTimeout( function() {
+							$wrap.removeClass('closed'); },
+						100 );
+					});
+
+					$($wrap).mouseout(function() {
+						clearTimeout(hashoverover);
+					});
 				}
 			},