$(document).ready(function($){
	initRollOverImages();
});



function initRollOverImages() {  
	var image_cache = new Object();  
	$(".ro a img").not("[src*='_on.']").each(function(i) {  
		var imgsrc = this.src;  
		var dot = this.src.lastIndexOf('.');  
		var imgsrc_on = this.src.substr(0, dot) + '_on' + this.src.substr(dot, 4);  
		image_cache[this.src] = new Image();  
		image_cache[this.src].src = imgsrc_on;  
		$(this).hover(  
			function() { this.src = imgsrc_on; },  
			function() { this.src = imgsrc; }  
		);  
	});  
}