// load events when dom is ready
$(function(){
// attach events to nav links
if($(".roll")){
// mouseover image replacement
$(".roll").bind("mouseover", function(){
if(this.src){
if(this.src.indexOf("-over.gif") != -1){ this.src = this.src.substr(0, this.src.indexOf("-over.gif")) + ".gif";}
  else {this.src = this.src.substr(0, this.src.indexOf(".gif")) + "-over.gif";}  
}
  

  });

// mouseout
$(".roll").bind("mouseout", function(){

if(this.src){
 if(this.src.indexOf("-over.gif") != -1){ this.src = this.src.substr(0, this.src.indexOf("-over.gif")) + ".gif";}
  else {this.src = this.src.substr(0, this.src.indexOf(".gif")) + "-over.gif";}  
}
 

  });
}
});