Menu Hover Image

Hi,
How can I use an image for a menu Item and another image when the item is hover???
<asp:Menu ID="Menu1" runat="server" DataSourceID="SiteMapDataSource1">             <StaticMenuStyle CssClass=" StaticMenuStyle" />             <StaticMenuItemStyle CssClass="StaticMenuItemStyle" />         </asp:Menu>

    <siteMapNode url="Default" title="Home"  description="">         <siteMapNode url="~/Default.aspx" title="Home"  description="" />         <siteMapNode url="~/Prodotti.aspx" title="Prodotti"  description=&quo ...