function ddown(ly)
	{ 
 	    if(document.getElementById(ly) != null)
 	        document.getElementById(ly).style.display = 'block';
	}
    
    function dhide(ly)
	{
	    if(document.getElementById(ly))
 	        document.getElementById(ly).style.display = 'none';
    }

    if (document.layers)
        window.captureEvents(Event.MOUSEDOWN);
    
    var isNS = (navigator.appName == "Netscape") ? 1 : 0;
    if (navigator.appName == "Netscape") document.captureEvents(Event.MOUSEDOWN || Event.MOUSEUP);
    function mischandler()
    {
        return false;
    }

    function mousehandler(e)
    {
        var myevent = (isNS) ? e : event;
        var eventbutton = (isNS) ? myevent.which : myevent.button;
        if ((eventbutton == 2) || (eventbutton == 3)) return false;
    }
    
    document.oncontextmenu = mischandler;
    document.onmousedown = mousehandler;
    document.onmouseup = mousehandler;