var message="Tasto destro disabilitato!";                         
                                                                  
///////////////////////////////////                               
function clickIE4(){                                              
if (event.button==2){                                             
alert(message);                                                   
return false;                                                     
}                                                                 
}                                                                 
                                                                  
function clickNS4(e){                                             
if (document.layers||document.getElementById&&!document.all){     
if (e.which==2||e.which==3){                                      
alert(message);                                                   
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("alert(message);return false")