diff --git a/cocos2d/actions/CCActionInterval.js b/cocos2d/actions/CCActionInterval.js
index 905d72b0a2..e6b86ea906 100644
--- a/cocos2d/actions/CCActionInterval.js
+++ b/cocos2d/actions/CCActionInterval.js
@@ -3393,8 +3393,8 @@ cc.Animate = cc.ActionInterval.extend(/** @lends cc.Animate# */{
         var numberOfFrames = frames.length, locSplitTimes = this._splitTimes;
         for (var i = this._nextFrame; i < numberOfFrames; i++) {
             if (locSplitTimes[i] <= dt) {
-                _currFrameIndex = i;
-                this.target.setSpriteFrame(frames[_currFrameIndex].getSpriteFrame());
+                this._currFrameIndex = i;
+                this.target.setSpriteFrame(frames[this._currFrameIndex].getSpriteFrame());
                 this._nextFrame = i + 1;
             } else {
                 // Issue 1438. Could be more than one frame per tick, due to low frame rate or frame delta < 1/FPS
diff --git a/cocos2d/core/platform/CCInputExtension.js b/cocos2d/core/platform/CCInputExtension.js
index e61f58459a..882baf6576 100644
--- a/cocos2d/core/platform/CCInputExtension.js
+++ b/cocos2d/core/platform/CCInputExtension.js
@@ -136,4 +136,4 @@ _p.didAccelerate = function (eventData) {
     }
 };
 
-delete _p;
\ No newline at end of file
+_p = null;
\ No newline at end of file
diff --git a/cocos2d/core/platform/CCScreen.js b/cocos2d/core/platform/CCScreen.js
index 8bc1e4d758..cecf6a13b9 100644
--- a/cocos2d/core/platform/CCScreen.js
+++ b/cocos2d/core/platform/CCScreen.js
@@ -82,7 +82,7 @@ cc.screen = /** @lends cc.screen# */{
     init: function () {
         this._fn = {};
         var i, val, map = this._fnMap, valL;
-        for (i = 0, l = map.length; i < l; i++) {
+        for (i = 0; i < map.length; i++) {
             val = map[i];
             if (val && val[1] in document) {
                 for (i = 0, valL = val.length; i < valL; i++) {