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) {
		iserv_o = newImage("images/iserv_o.gif");
		isafe_o = newImage("images/isafe_o.gif");
		imssn_o = newImage("images/imssn_o.gif");
		iproj_o = newImage("images/iproj_o.gif");
		icomp_o = newImage("images/icomp_o.gif");
		iref_o = newImage("images/iref_o.gif");
		icont_o = newImage("images/icont_o.gif");
		preloadFlag = true;
	}
}