function imgMouseOverEvents(outString, overString, selector) {
	$$(selector).each(function(image) {
		image = $(image);
		if (image.hasClass('active'))
			{
			 if ($type(image.src)) image.src = image.src.replace(outString, overString);
			}		
		if ($type(image.src)) {
			if (image.src.indexOf(outString) > 0) {
				image.addEvent('mouseenter',function(){
					image.src = image.src.replace(outString, overString);
				}).addEvent('mouseleave', function(){
					image.src = image.src.replace(overString, outString);
				});
			}
		}
	});
};

window.addEvent('domready', function(){
	imgMouseOverEvents('_off', '_on', 'div#nav img, div#navchoice img');
	$$('a.external').each(function(el) {
		el.target = '_blank';
	});
});