var bNS = (navigator.appName == 'Netscape');
var bIE = (navigator.appName == 'Microsoft Internet Explorer');

var selbutton = -1;

var imgnames = new Array();
imgnames[0] = "ff9";
imgnames[1] = "ff8";
imgnames[2] = "ff7";
imgnames[3] = "misc";

var imgs = new Array();
imgs[0] = new Image;       imgs[0].src = "btn_ff9_1.jpg";
imgs[1] = new Image;       imgs[1].src = "btn_ff8_1.jpg";
imgs[2] = new Image;       imgs[2].src = "btn_ff7_1.jpg";
imgs[3] = new Image;       imgs[3].src = "btn_misc_1.jpg";

var hoverimgs = new Array();
hoverimgs[0] = new Image;  hoverimgs[0].src = "btn_ff9_2.jpg";
hoverimgs[1] = new Image;  hoverimgs[1].src = "btn_ff8_2.jpg";
hoverimgs[2] = new Image;  hoverimgs[2].src = "btn_ff7_2.jpg";
hoverimgs[3] = new Image;  hoverimgs[3].src = "btn_misc_2.jpg";

var selimgs = new Array();
selimgs[0] = new Image;    selimgs[0].src = "btn_ff9_3.jpg";
selimgs[1] = new Image;    selimgs[1].src = "btn_ff8_3.jpg";
selimgs[2] = new Image;    selimgs[2].src = "btn_ff7_3.jpg";
selimgs[3] = new Image;    selimgs[3].src = "btn_misc_3.jpg";


function setdoc (index, action) {
//   if (bNS)
//      eval("document.layers['"+index+"']."+action+";");
//   else if (bIE)
      eval("document.all['"+index+"']."+action+";");
//   else
//      eval("document."+index+"."+action+";");
}

function setimg (index, img) {
   eval("document.images['"+index+"'].src = img;");
}

function btn (n) {
   if (bIE) {
      if (selbutton == n) {
         setdoc("div_"+imgnames[n], "style.visibility = 'hidden'");
         setimg("btn_"+imgnames[n], hoverimgs[n].src);
         selbutton = -1;
      } else {
         if (selbutton != -1) {
            setdoc("div_"+imgnames[selbutton], "style.visibility = 'hidden'");
            setimg("btn_"+imgnames[selbutton], imgs[selbutton].src);
         }
         setimg("btn_"+imgnames[n], selimgs[n].src);
         setdoc("div_"+imgnames[n], "style.visibility = ''");
         selbutton = n;
      }
   } else {
      window.open("#"+imgnames[n], '_self');
   }
}

function hover (n) {
   if (selbutton != n) {
      setimg("btn_"+imgnames[n], hoverimgs[n].src);
   }
}

function unhover (n) {
   if (selbutton != n) {
      setimg("btn_"+imgnames[n], imgs[n].src);
   }
}