ie tester 加载firebug lite

先执行

var s = document.createElement("script");  
s.src = 'http://getfirebug.com/releases/lite/1.2/firebug-lite-compressed.js';  
s.type="text/javascript";  
if(document.all){  
   s.onreadystatechange = function(){  
    if(this.readyState == "loaded" || this.readyState == "complete"){  
     alert("loaded success in ie");  
    }  
   }  
} else {  
   s.onload = function(){  
    alert("load success");  
   }  
}  
document.body.appendChild(s);

再执行初始化方法

firebug.init();