function showLayer( layerId ){
	if( layerId == currentLayerId )
		return false;
	var newLayer = document.getElementById(layerId);
	newLayer.style.display='inline';
	var currentLayer = document.getElementById( currentLayerId );
	currentLayer.style.display='none';
	currentLayerId = layerId;
	return false;
}

function imageSwap(imagename, imagesource){
  var objStr,obj;
  if(document.images){
    if (typeof(imagename) == 'string') {
      objStr = 'document.' + imagename;
      obj = eval(objStr);
      obj.src = imagesource;
    } else if ((typeof(imagename) == 'object') && imagename && imagename.src) {
      imagename.src = imagesource;
    }
  }
}