Currently in IE9 dragging an element does select the text because document.selection.empty() does fire to early. Adding the timeout fixes this problem.

Sortable.js

@@ -402,7 +402,10 @@
 
 			try {
 				if (document.selection) {					
-					document.selection.empty();
+					// Timeout neccessary for IE9					
+					setTimeout(function () {
+						document.selection.empty();
+					});					
 				} else {
 					window.getSelection().removeAllRanges();
 				}