normal1 = new Image();
normal1.src = "img/bt_leistungen_u.gif";     
rollover1 = new Image();
rollover1.src = "img/bt_leistungen_ro.gif"; 

normal2 = new Image();
normal2.src = "img/bt_mitglieder_u.gif";     
rollover2 = new Image();
rollover2.src = "img/bt_mitglieder_ro.gif"; 

normal3 = new Image();
normal3.src = "img/bt_antrag_u.gif";     
rollover3 = new Image();
rollover3.src = "img/bt_antrag_ro.gif"; 

function changeImg (name, imgObj) {
	window.document.images[name].src = imgObj.src;
}