var current_banner = 'banner1'

function rotate_index_banners()
{
    window.setTimeout('rotate_index_banner()', 4000)
}

function rotate_index_banner()
{
    b_out = current_banner
    b_in  = (current_banner == 'banner1') ? 'banner2' : 'banner1'
    Effect.Fade(b_out, { duration : .5})
    Effect.Appear(b_in, { duration : .5, queue : 'end' })
    current_banner = b_in
    window.setTimeout('rotate_index_banner()', 4000)
}