// overide the default prototype show() and hide() methods to use css instead of inline styles

Element.addMethods({
    show : function(element) {
        element = $(element);
        element.removeClassName('hide').setStyle({display: ''});
        return element;
    },
    hide : function(element) {
        element = $(element);
        element.addClassName('hide').setStyle({display: 'none'});
        return element;         
    }
});