var buttons = new Array("pdi", "khc", "ei", "sdds", "pc");
var x = 0;

function ButtonSwap() {
Effect.Fade(buttons[x], { duration:1, from:1.0, to:0.0 });
    x++;
    if (x == 5) x = 0;
    Effect.Appear(buttons[x], { duration:1, from:0.0, to:1.0 });
}
function start() {
setInterval("ButtonSwap()", 2000); 
}

window.onload = start;