if (document.images) {
uvodon = new Image();
uvodon.src = "images/hlavicka1on.jpg";
uvodoff = new Image();
uvodoff.src = "images/hlavicka1off.jpg";
servison = new Image();
servison.src = "images/hlavicka2on.jpg";
servisoff = new Image();
servisoff.src = "images/hlavicka2off.jpg";
grafikaon = new Image();
grafikaon.src = "images/hlavicka3on.jpg";
grafikaoff = new Image();
grafikaoff.src = "images/hlavicka3off.jpg";
hostingon = new Image();
hostingon.src = "images/hlavicka4on.jpg";
hostingoff = new Image();
hostingoff.src = "images/hlavicka4off.jpg";
kontakton = new Image();
kontakton.src = "images/hlavicka5on.jpg";
kontaktoff = new Image();
kontaktoff.src = "images/hlavicka5off.jpg";
}
	function imgOn(imgName) {
	if (document.images) {
	document[imgName].src = eval(imgName + "on.src");
		}
	}
	function imgOff(imgName) {
	if (document.images) {
	document[imgName].src = eval(imgName + "off.src");
		}
	}