diff --git a/ui/jquery.ui.dialog.js b/ui/jquery.ui.dialog.js
index 6d13935de..0d48c1cf7 100644
--- a/ui/jquery.ui.dialog.js
+++ b/ui/jquery.ui.dialog.js
@@ -66,8 +66,12 @@ $.widget("ui.dialog", {
 				// setting tabIndex makes the div focusable
 				// setting outline to 0 prevents a border on focus in Mozilla
 				.attr('tabIndex', -1).css('outline', 0).keydown(function(event) {
-					(options.closeOnEscape && event.keyCode
-						&& event.keyCode == $.ui.keyCode.ESCAPE && self.close(event));
+					if (options.closeOnEscape && event.keyCode
+						&& event.keyCode == $.ui.keyCode.ESCAPE) {
+						
+						self.close(event);
+						event.preventDefault();
+					}
 				})
 				.attr({
 					role: 'dialog',
@@ -614,8 +618,12 @@ $.extend($.ui.dialog.overlay, {
 
 			// allow closing by pressing the escape key
 			$(document).bind('keydown.dialog-overlay', function(event) {
-				(dialog.options.closeOnEscape && event.keyCode
-						&& event.keyCode == $.ui.keyCode.ESCAPE && dialog.close(event));
+				if (dialog.options.closeOnEscape && event.keyCode
+					&& event.keyCode == $.ui.keyCode.ESCAPE) {
+					
+					dialog.close(event);
+					event.preventDefault();
+				}
 			});
 
 			// handle window resize