$(document).ready(function(){
	$(".rollover").hover(
		function () {
			var oldsource = $("img", this).attr("src");
			var gifCheck = oldsource.indexOf('.gif');
			var jpgCheck = oldsource.indexOf('.jpg');
			var pngCheck = oldsource.indexOf('.png');
			if ( gifCheck > 0 ) {	var newsource = oldsource.replace(".gif", "-over.gif");	}
			else if ( jpgCheck > 0 ) {	var newsource = oldsource.replace(".jpg", "-over.jpg");	}
			else if ( pngCheck > 0 ) {	var newsource = oldsource.replace(".png", "-over.png");	}
			else {	var newsource = oldsource;	}
			$("img", this).attr("src", newsource);
		}, 
		function () {
			var oldsource = $("img", this).attr("src");
			var overCheck = oldsource.indexOf('-over');
			if ( overCheck > 0 ) {	var newsource = oldsource.replace("-over", "");	}
			else {	var newsource = oldsource;	}
			$("img", this).attr("src", newsource);
		}
	);
});