function initArray() {
this.length = initArray.arguments.length;
for (var i = 0; i < this.length; i++) {
this[i] = initArray.arguments[i];
   }
}


var speed = 1000;
var x = 0;
var color = new initArray(
"red", 
"blue", 
"green",
"black"
);


function chcolor(){ 
document.all.c.style.color = color[x];
(x < color.length-1) ? x++ : x = 0;
}



setInterval("chcolor()",1000);