function setplayer(what){
    document.cookie="silverlight="+what;
}

function isSilverlightInstalled(){
     var isSilverlightInstalled = false;
     try{
          //check on IE
          try{
               var slControl = new ActiveXObject('AgControl.AgControl');
                isSilverlightInstalled = true;
           }
           catch (e){
                //either not installed or not IE. Check Firefox
                if ( navigator.plugins["Silverlight Plug-In"] ) {
                     isSilverlightInstalled = true;
                 }
            }
       }
       catch (e){
            //we don't want to leak exceptions. However, you may want
             //to add exception tracking code here.
        }
       
         setplayer(isSilverlightInstalled);
         return isSilverlightInstalled;
}