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;