window.onload = rollover;  
   
 function rollover() {  
     if(!document.getElementById && document.getElementsByTagName) return false;  
       
     if (document.getElementById("mouseovers")) {  
         var source = document.getElementById("mouseovers");  
         var images = source.getElementsByTagName("img");  
           
         for (var i=0; i < images.length; i++) {  
             var suffix = images[i].src.substring(images[i].src.lastIndexOf('.'));  
             var prefix = images[i].src.slice(0,images[i].src.length - suffix.length);  
             imgload = new Image();  
             imgload.src = prefix+"_on"+suffix;  
         }  
           
         for (var i=0; i < images.length; i++) {  
             images[i].onmouseover = function() {  
                 var suffix = this.src.substring(this.src.lastIndexOf('.'));  
                 var prefix = this.src.slice(0,this.src.length - suffix.length);  
                 this.src = prefix+"_on"+suffix;  
             }  
               
             images[i].onmouseout = function() {  
                 this.src = this.src.replace("_on", '');  
             }     
         }  
     }  
	 
/*	 	var trunc1 = document.getElementById("mouseovers");
		var trunc2 = trunc1.getElementsByTagName("img");
		

		for(i=0,i<trunc2.length,i++){
		var chkstr = trunc[i].src.substring(0,1);

		if(chkstr="_") {
			return;
		}
	}*/
 }