var core = 0;

function initArray() {

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

link4 = new initArray(
"http://www.smarterflush.com/",
"#"
);

image4 = new initArray(
"/sponsorimages/smarterflushlogo.jpg",
"/sponsorimages/sponsorad.jpg"
);

text4 = new initArray(
"Smarter Flush Logo",
"Your Ad Here"
);

var core = (Math.floor(Math.random()*2));
var ranlink  = link4[core];
var ranimage = image4[core];
var rantext  = text4[core];

document.write('<a id="bannerlink4" href=\"' +ranlink+ '\" target="_blank"><img id="banner4" src=\"'+ranimage+'\" border="0" alt=\"'+rantext+'\"></a>');

function changeImage4() {
var core = (Math.floor(Math.random()*2));
var ranlink  = link4[core];
var ranimage = image4[core];
var rantext  = text4[core];

document.getElementById('bannerlink4').href = ranlink;
document.getElementById('banner4').src = ranimage;
document.getElementById('banner4').alt = rantext;
setTimeout("changeImage4()", 6000);
}

changeImage4();