<!--
 mac = (navigator.appVersion.indexOf("Mac") != -1);        
     ns4 = (document.layers)? true:false  
     dom = (document.getElementById) ? true : false;  
      ie = (document.all)? true:false  
     ie4 = ie && !dom  
     ie5 = (ie && dom)  
     ns6 = (!ie && dom)  
       
     // Verifica versao do IE  
if (ie4) {  
     if (navigator.userAgent.indexOf('MSIE 5')>0) {  
          ie5 = true;  
     } else {  
          ie5 = false; }  
} else {  
     ie5 = false;  
}
//-->