Ajax跨域访问后回调函数的问题

Ajax跨域访问bing translator的接口，在url中后面直接加上oncompete=mycallback，但是回调函数却不执行，、、、、、、顺便给解释一下oncomplete，这到底是哪的方法？？？

 <script type="text/javascript">   function loadXMLDoc(){	xmlHttpRequest=null;	if (window.XMLHttpRequest)	  {// code for IE7, Firefox, Opera, etc.	       	      xmlHttpRequest=new XMLHttpRequest();	  }	else if (window.ActiveXObject)	  {// code for IE6, IE5	      xmlHttpRequest=new ActiveXObject("Microsoft.XMLHTTP");	  }	 if (xmlHttpRequest!=null)	  {   	      xmlHttpRequest.open("GET","AjaxSer",true); 	      xmlHttpRequest.onreadystatechange=state_Change;	      xmlHttpRequest.send(null);	  }     else	  {	    alert("Your browser does not support XMLHTTP.");	  }     function state_Change()        {             if(xmlHttpRequest.readyState == 4 && xmlHttpRequest.status == 200){                      var responseText = xmlHttpRequest.responseText;            var from = "en", to = "Zh-CHS", text = "i love you , China";            var s = document.createElement("script");                        s.src = "http://api.microsofttranslator.com/V2/Ajax.svc/Translate" +                "?appId=Bearer " + encodeURIComponent(responseText) +                "&from=" + encodeURIComponent(from) +                "&to=" + encodeURIComponent(to) +                "&text=" + encodeURIComponent(text) +                "&oncomplete=mycallback";             document.body.appendChild(s);                        }        }       function mycallback(r){          alert(r);          document.getElementById("div2").innerHTML = r ;       }             }     </script>