if (document.getElementById) document.oncontextmenu = showCrMessage;

// otherwise distinguish between NS 4 and MSIE 4
else
{
document.onmousedown=disableRightClick;
if (document.layers) 
window.captureEvents(Event.MOUSEDOWN);
window.onmousedown=disableRightClick;
}

function showCrMessage()
{
alert("Copyrighted - Contact us for permission to use this information");
return false;
}

function disableRightClick(event)
{
if (navigator.appName == 'Netscape' && (event.which == 3 || event.which == 2))
{
alert("Copyrighted - Contact us for permission to use this information");
return false;
}
else if (navigator.appName == 'Microsoft Internet Explorer' && (event.button == 2 || event.button == 3))
{
alert("Copyrighted - Contact us for permission to use this information");
return false;
}
else return true;
}