if (window.Event)
document.captureEvents(Event.MOUSEUP);
function nocontextmenu() 
{
event.cancelBubble = true
event.returnValue = false;
return false; }

function norightclick(e)
{
if (window.Event)
{
if (e.which == 2 || e.which == 3)
return false;
} else
if (event.button == 2 || event.button == 3)
{ event.cancelBubble = true
event.returnValue = false;
return false;
}
}

document.oncontextmenu = nocontextmenu; 
document.onmousedown = norightclick;