function rollOver(src) 
{
  document.getElementById(src).src = "images/" + src + "_RO.gif";
}
function rollOut(src) {
  document.getElementById(src).src = "images/" + src + ".gif";
}


function rollOverByLevel(src, lvl) 
{
  document.getElementById(src).src = lvl + "images/" + src + "_RO.gif";
}
function rollOutByLevel(src, lvl) {
  document.getElementById(src).src = lvl + "images/" + src + ".gif";
}