if(typeof(PRI) == 'undefined')
    PRI = {};
PRI.ir = function(cl, ext, dir) {
    Event.observe(window, 'load', function () {
    if(!dir.match(/\/$/))
        dir += '/';
    $$('.' + cl).each(function(e){
        var img = new Image();
        var img_e = document.createElement('img');
        img.src = dir + e.id + '.' + ext;
        img_e.src = img.src;
        img_e.alt = e.innerHTML.replace(/<.*?>/g,'').escapeHTML();
        e.innerHTML = '';
        e.appendChild(img_e);
    });
    });
}