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) {
		facebook_on = newImage("/themes/eucalyptus/img/facebook_on.png");
		facebook_off = newImage("/themes/eucalyptus/img/facebook_off.png");
		twitter_on = newImage("/themes/eucalyptus/img/twitter_on.png");
		twitter_off = newImage("/themes/eucalyptus/img/twitter_off.png");
		tab_opensource_on = newImage("/themes/eucalyptus/img/tab_opensource_on.png");
		tab_opensource_off = newImage("/themes/eucalyptus/img/tab_opensource_off.png");
		tab_corporate_on = newImage("/themes/eucalyptus/img/tab_corporate_on.png");
		tab_corporate_off = newImage("/themes/eucalyptus/img/tab_corporate_off.png");
		preloadFlag = true;
	}
}