obr1 = new Image();
obr1.src = '/obrazky/architektura-hover.gif';
obr2 = new Image();
obr2.src = '/obrazky/inzenyring-hover.gif';
obr3 = new Image();
obr3.src = '/obrazky/dozor-hover.gif';
obr4 = new Image();
obr4.src = '/obrazky/dotace-hover.gif';

var nPreloadedImages = 0;
var arImgs = new Array();

function insertHoverImage(imgA_src,imgB_src,width,height){
	arImgs[nPreloadedImages] = new Image();
	arImgs[nPreloadedImages].src = imgB_src;
	document.write('<img src="'+imgA_src+'" onmouseover="this.src=arImgs['+nPreloadedImages+'].src" onmouseout="this.src=\''+imgA_src+'\'" width="'+width+'" height="'+height+'" alt="" />');
	nPreloadedImages++;
}