if (Prototype.Browser.IE==true) {
   document.observe('selectstart', function(e) { 
      var e = e || window.event;
      if (e.srcElement.nodeName!='INPUT' && e.srcElement.nodeName!='TEXTAREA') {
         document.selection.clear();  
         return false;
      }
   });
   
   document.observe('keyup', function (event){
         var event = event || window.event;
         var sender = event.target || event.srcElement;
         if (sender.tagName.match(/INPUT|TEXTAREA/i))
         return;
         var key = event.keyCode || event.which;
         if (event.ctrlKey && key == 'A'.charCodeAt(0))
            {
               document.selection.empty();  
               if (event.preventDefault)
               event.preventDefault();
               else
               event.returnValue = false;
            }
         
   });
   
    document.observe('keydown', function (event){
      var event = event || window.event;
      if (event.srcElement.nodeName.match(/INPUT|TEXTAREA/i))
         return;
         document.selection.empty();
         return false;
         
   });


}
else if (Prototype.Browser.Opera==true) {
   document.observe('mousemove', function(e) { 
         if (e.target.ownerDocument.defaultView.getSelection) { 
            e.target.ownerDocument.defaultView.getSelection().removeAllRanges(); 
            }     

         return false;
   });
  
}