diff --git a/lib/std.js b/lib/std.js
index dfecf69..ebb5585 100644
--- a/lib/std.js
+++ b/lib/std.js
@@ -307,13 +307,30 @@ function StdEventableObject() {
 };
 
 function AsyncFunction(f) {
+    this.htmlfile = null;
+    this.proxyWindow = null;
     this.f = f;
+
     this.run = function() {
-        sleep(1, this.f);
+        if (this.proxyWindow != null) {
+            this.proxyWindow.setTimeout(1, this.f);
+        } else {
+            sleep(1, this.f);
+        }
     };
     this.runSynchronously = function() {
-        return this.f();
+        return this.f.apply(null, arguments);
     };
+
+    // https://qiita.com/abcang/items/80b5733b5a96eeff9945
+    if (typeof WScript !== "undefined") {
+        try {
+            this.htmlfile = CreateObject("htmlfile");
+            this.proxyWindow = this.htmlfile.parentWindow;
+        } catch (e) {
+            console.warn("AsyncFunction require HTMLFILE object in WScript");
+        }
+    }
 };
 
 global.GetResource = GetResource;
@@ -326,9 +343,9 @@ global.splitLn = splitLn;
 global.addslashes = addslashes;
 global.AsyncFunction = AsyncFunction;
 
-exports.VERSIONINFO = "Standard Lib (std.js) version 0.4";
+exports.VERSIONINFO = "Standard Lib (std.js) version 0.5";
 exports.global = global;
 exports.require = global.require;
 
 exports.Event = StdEvent;
-exports.EventableObject = StdEventableObject;
\ No newline at end of file
+exports.EventableObject = StdEventableObject;