function clickButton(e, buttonid)
{ 
  var bt = document.getElementById(buttonid); 
  if (typeof bt == 'object'){ 
        if(navigator.appName.indexOf("Netscape")>(-1)){ 
              if (e.keyCode == 13){ 
                    bt.click(); 
                    return false; 
              } 
        } 
        if (navigator.appName.indexOf("Microsoft Internet Explorer")>(-1)){ 
              if (event.keyCode == 13){ 
                    bt.click(); 
                    return false; 
              } 
        } 
    } 
}