Forgot to make sure that oldData actually had data in it before the copy attempt.

src/manipulation.js

@@ -283,7 +283,7 @@ function cloneCopyEvent(orig, ret) {
 			return;
 		}
 
-		var oldData = jQuery.data( orig[i++] ), curData = jQuery.data( this, oldData ), events = oldData.events;
+		var oldData = jQuery.data( orig[i++] ), curData = jQuery.data( this, oldData ), events = oldData && oldData.events;
 
 		if ( events ) {
 			delete curData.handle;