//画像のpreload
if (document.images) {
  var dir = "/img/"; //画像のパス
  var onimg  = new Array("global-navigation_btn001o.gif", "global-navigation_btn002o.gif", "global-navigation_btn003o.gif", "global-navigation_btn004o.gif", "global-navigation_btn005o.gif")
  var offimg = new Array("global-navigation_btn001.gif", "global-navigation_btn002.gif", "global-navigation_btn003.gif", "global-navigation_btn004.gif", "global-navigation_btn005.gif")
  var onsel = new Array();
  var offsel = new Array();
  for (i = 0; i < onimg.length; i++) {
    onsel[i] = new Image();         offsel[i] = new Image();
    onsel[i].src = dir + onimg[i];  offsel[i].src = dir + offimg[i];
  }
}

//イメージオブジェクト
function onSelect(n) {
  if (document.images) {
    document.images["gnav" + n].src=onsel[n].src;
  }
}

function offSelect(n) {
  if (document.images) {
    document.images["gnav" + n].src=offsel[n].src;
  }
}