function changeImages(imgName, imgSrc) 

{
var merker = '';
var Startmerker = '';
if (document.images)
{ 
	merkerFeld = 'button2_' + merker;
	if (imgSrc != 'none' && imgName != merkerFeld)
	{
		document.images[imgName].src = imgSrc;
	}
}
}