var mensagem="";
function clickIE()  {if (document.all) {(mensagem);return false;}}
function clickNS(e) {if 
             (document.layers||(document.getElementById&&!document.all)) {
          if (e.which==2||e.which==3) {(mensagem);return false;}}}
          if (document.layers) 
             {document.captureEvents(Event.MOUSEDOWN);document.onmousedown=clickNS;}
        else {document.onmouseup=clickNS;document.oncontextmenu=clickIE;}
              document.oncontextmenu=new Function("return false")