function RestoreImage() 
{ 
  if (document.SwapImgData != null)
    for (var i=0; i<(document.SwapImgData.length-1); i+=2)
      document.SwapImgData[i].src = document.SwapImgData[i+1];
}

function PreloadImages() 
{ 
  if (document.images) {
    var imgFiles = PreloadImages.arguments;
    if (document.preloadArray==null) document.preloadArray = new Array();
    var i = document.preloadArray.length;
    with (document) for (var j=0; j<imgFiles.length; j++) if (imgFiles[j].charAt(0)!="#"){
      preloadArray[i] = new Image;
      preloadArray[i++].src = imgFiles[j];
  } }
}

function SwapImage() 
{ 
  var i,j=0,objStr,obj,swapArray=new Array,oldArray=document.SwapImgData;
  for (i=0; i < (SwapImage.arguments.length-2); i+=3) {
    objStr = SwapImage.arguments[(navigator.appName == 'Netscape')?i:i+1];
    if ((objStr.indexOf('document.layers[')==0 && document.layers==null) ||
        (objStr.indexOf('document.all[')   ==0 && document.all   ==null))
      objStr = 'document'+objStr.substring(objStr.lastIndexOf('.'),objStr.length);
    obj = eval(objStr);
    if (obj != null) {
      swapArray[j++] = obj;
      swapArray[j++] = (oldArray==null || oldArray[j-1]!=obj)?obj.src:oldArray[j];
      obj.src = SwapImage.arguments[i+2];
  } }
  document.SwapImgData = swapArray; 
}


function FosterMenuChange(vMenuItem, vMenuImage, vCenterImage) 
{ 

 SwapImage('document.centerimage','document.centerimage',vCenterImage);
SwapImage(vMenuItem,vMenuItem,vMenuImage);
}

function FosterMenuRestore() 
{ 
RestoreImage();
 document.centerimage.src = 'img/centerblank.jpg';
}