window.addEvent('domready', function() {

    /*
     * Internet Explorer 6 PNG
     */
    if (Browser.Engine.trident4)
    {
        $$('img.png-change').each(function(element) {
            element.set('src', element.get('src').replace(/\.png/i, '.gif'));
        });

    }
    
    if ($('header-navigation'))
    {
        $('header-navigation').getElements('li').each(function(element) {

            if (!element.hasClass('active'))
            {
                element.addEvent('mouseover', function() {
                    var image = this.getElements('a img')[0];
                    
                    image.set('src', image.get('src').replace(/default/i, 'active'));
                });
                
                element.addEvent('mouseout', function() {
                    var image = this.getElements('a img')[0];
                    
                    image.set('src', image.get('src').replace(/active/i, 'default'));
                });
            } 
            
            new Image().src = element.getElements('a img')[0].get('src').replace(/default/i, 'active');
            
        });
    }
    
});