over = function() {
	var sfEls = document.getElementById("nav").getElementsByTagName("LI");
	for (var i=0; i<sfEls.length; i++) {
		sfEls[i].onmouseover=function() {
			this.className+=" over";
		}
		sfEls[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp("over"), "");
		}
	}
}
if (window.attachEvent) window.attachEvent("onload", over);


function back_() {
 	if (back_num < 0)
	{
		back_num = imageArray.length -1;
	}

	showpic(imageArray[back_num]);
	back_num--;
  }


  function for_ward() {
 	if (for_num >=imageArray.length)
	{
		for_num = 0;
	}

	showpic(imageArray[for_num]);
	for_num++;	
  }