function clickIE4()
{
  if (event.button==2)
  {
    return false;
  }
}
function clickNS4(e)
{
  if (document.layers||document.getElementById&&!document.all)
  {
  if (e.which==2||e.which==3)
    {
    return false;
    }
  }
}
if (document.layers)
{
  document.captureEvents(Event.MOUSEDOWN);
  document.onmousedown=clickNS4;
}
else if (document.all&&!document.getElementById)
{
  document.onmousedown=clickIE4;
}
document.oncontextmenu=new Function("return false")