function FilterEnter(e)
{  var characterCode;

   if(e && e.which)
   {  e = e;
      characterCode = e.which;
   }
   else
   {  e = event;
      characterCode = e.keyCode;
   }

   if(characterCode == 13)
   {  return false;
   }
   else
   {  return true; 
   }
}