diff --git a/lib/client/rest.js b/lib/client/rest.js
index f91f87f5..880f07d3 100644
--- a/lib/client/rest.js
+++ b/lib/client/rest.js
@@ -123,13 +123,12 @@ var Util, DOM, CloudFunc, CloudCmd;
             CloudCmd.getConfig(function(config) {
                 var data,
                     isString        = Util.isString(p.data),
-                    isArrayBuffer   = Util.isArrayBuffer(p.data),
                     isFile          = Util.isFile(p.data);
                 
                 if (Util.isString(p.url))
                     p.url = decodeURI(p.url);
                 
-                if (p.data && !isString  && !isArrayBuffer && !isFile)
+                if (p.data && !isString  && !isFile)
                     data = Util.stringifyJSON(p.data);
                 else
                     data = p.data;
diff --git a/lib/client/zip.js b/lib/client/zip.js
index 7c71c0c6..a99dbc98 100644
--- a/lib/client/zip.js
+++ b/lib/client/zip.js
@@ -9,13 +9,9 @@ var Util, Zip, pako;
    
    function ZipProto() {
         this.pack = function(str, callback) {
-            var buf, deflate, result,
-                isArray = Util.isArrayBuffer(str);
+            var buf, deflate, result;
             
-            if (isArray)
-                buf = str;
-            else
-                buf = utf8AbFromStr(str);
+            buf     = utf8AbFromStr(str);
             
             deflate = new pako.Deflate({
                 gzip:true
diff --git a/lib/util.js b/lib/util.js
index 46fa2741..744746c9 100644
--- a/lib/util.js
+++ b/lib/util.js
@@ -575,15 +575,7 @@
          * @param variable
          */
         this.isArray                = function(variable) {
-            return variable instanceof Array;
-        };
-        
-        /**
-         * functions check is variable is ArrayBuffer
-         * @param variable
-         */
-        this.isArrayBuffer          = function(variable) {
-            return variable instanceof ArrayBuffer;
+            return Array.isArray(variable);
         };
         
         /**