window.onload = init_change_image;
var origImg;

function init_change_image() {
	var rollOverId;
  var imgObj = document.getElementById("home_sign_image");
  origImg = document.getElementById("home_sign_image");
  for (var i=0; i<document.links.length; i++) {
    var linkObj = document.links[i];
    if (linkObj.className == "image_change") {
  		for (var j=0; j<linkObj.childNodes.length; j++) {
				if (linkObj.childNodes[j].className=="rollover") {
					rollOverId = linkObj.childNodes[j].id;
					break;
				}
			}
			var signImg = "images/nav/" + linkObj.id + "-sign.gif";
			var theRolloverImg = "images/nav/" + rollOverId + "-over.jpg";
			setupRolloverImgs(imgObj,linkObj,signImg, rollOverId, theRolloverImg);
    }
  }
}

function setupRolloverImgs (theImage, thisLink, theNewImage, rollOverId, theRolloverImg) {
	thisLink.rollOverId = rollOverId;
	thisLink.theRolloverImg = theRolloverImg;
  thisLink.imgToChange = theImage;
  thisLink.onmouseout = rollOutImg
  thisLink.onmouseover = rollOverImg;
  thisLink.outImage = new Image();
  thisLink.outImage.src = origImg.src;
  thisLink.overImage = new Image();
  thisLink.overImage.src = theNewImage;
}

function rollOverImg() {
  this.imgToChange.src = this.overImage.src;
	MM_swapImage(this.rollOverId,'', this.theRolloverImg,1);
}

function rollOutImg() {
  this.imgToChange.src = this.outImage.src;
	MM_swapImgRestore();
}


function MM_preloadImages() { //v3.0
  var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
    var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
    if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}

function MM_swapImgRestore() { //v3.0
  var i,x,a=document.MM_sr; for(i=0;a&&i<a.length&&(x=a[i])&&x.oSrc;i++) x.src=x.oSrc;
}

function MM_findObj(n, d) { //v4.01
  var p,i,x;  if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
    d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
  if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
  for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
  if(!x && d.getElementById) x=d.getElementById(n); return x;
}

function MM_swapImage() { //v3.0
  var i,j=0,x,a=MM_swapImage.arguments; document.MM_sr=new Array; for(i=0;i<(a.length-2);i+=3)
   if ((x=MM_findObj(a[i]))!=null){document.MM_sr[j++]=x; if(!x.oSrc) x.oSrc=x.src; x.src=a[i+2];}
}