function init() {
  enableHoverinIE6();
//  addEventHandlers();
}

function enableHoverinIE6() {
  if (document.all && document.getElementById) {
    navRoot = document.getElementById("navbar");
    for (i=0; i<navRoot.childNodes.length; i++) {
      node = navRoot.childNodes[i];
      node.onmouseover=function() {
        this.className+="over";
        //this.getElementsByTagName('ul')[0].style.display="block";
      }
      node.onmouseout=function() {
        this.className=this.className.replace("over", "");       
      }
    }
  }
}   

function addEventHandlers() {
  var images = document.getElementById('signup_btn').getElementsByTagName('img')[0]; 
  images.onmouseover = mouseGoesOver;
  images.onmouseout = mouseGoesOut; 
}   

function mouseGoesOver() {
  this.src = this.src.substring(0,this.src.lastIndexOf('.')) + "_over.png";
}

function mouseGoesOut() {
  this.src = this.src.substring(0,this.src.lastIndexOf('_')) + ".png";        
}
      
window.onload=init;