function setNavActive(navElementId) {
  document.getElementById(navElementId).className = "nav_header active";
  document.getElementById(navElementId + '_arrow').className = "arrow_active";
}

function setNavInactive(navElementId) {
  document.getElementById(navElementId).className = "nav_header";
  document.getElementById(navElementId + '_arrow').className = "arrow";
}

function setNavActiveNoArrow(navElementId) {
  document.getElementById(navElementId).className = "nav_header active";
}

function setNavInactiveNoArrow(navElementId) {
  document.getElementById(navElementId).className = "nav_header";
}

// functions for the rollover href images
function na_preload_img()
{
  var img_list = na_preload_img.arguments;
  if (document.preloadlist == null)
    document.preloadlist = new Array();
  var top = document.preloadlist.length;
  for (var i=0; i < img_list.length; i++) {
    document.preloadlist[top+i] = new Image;
    document.preloadlist[top+i].src = img_list[i+1];
  }
}

function na_change_img_src(name, nsdoc, rpath, preload)
{
  var img = eval((navigator.appName.indexOf('Netscape', 0) != -1) ? nsdoc+'.'+name : 'document.all.'+name);
  if (name == '')
    return;
  if (img) {
    img.altsrc = img.src;
    img.src    = rpath;
  }
}

function na_restore_img_src(name, nsdoc)
{
  var img = eval((navigator.appName.indexOf('Netscape', 0) != -1) ? nsdoc+'.'+name : 'document.all.'+name);
  if (name == '')
    return;
  if (img && img.altsrc) {
    img.src    = img.altsrc;
    img.altsrc = null;
  }
}