function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImages() {
	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		index_home_over = newImage("nav/index_home_over.png");
		index_serv_over = newImage("nav/index_serv_over.png");
		index_work_over = newImage("nav/index_work_over.png");
		index_team_over = newImage("nav/index_team_over.png");
		index_career_over = newImage("nav/index_career_over.png");
		index_test_over = newImage("nav/index_test_over.png");
		index_news_over = newImage("nav/index_news_over.png");
		index_cont_over = newImage("nav/index_cont_over.png");
		preloadFlag = true;
	}
}