diff --git a/lib/client/dom.js b/lib/client/dom.js
index cb09fc96..1a961cf9 100644
--- a/lib/client/dom.js
+++ b/lib/client/dom.js
@@ -216,6 +216,7 @@ var CloudCmd, Util, DOM, CloudFunc;
         },
         
         DOMTreeProto                = function() {
+            var DOM                     = this;
             /**
              * add class to element
              * 
@@ -303,11 +304,11 @@ var CloudCmd, Util, DOM, CloudFunc;
              * @param pElement
              */
             this.hide                    = function(pElement) {
-                return this.addClass(pElement, 'hidden');
+                return DOM.addClass(pElement, 'hidden');
             };
             
             this.show                    = function(pElement) {
-                this.removeClass(pElement, 'hidden');
+                return DOM.removeClass(pElement, 'hidden');
             };
         },