arr4 = new Array(
["http://www.petsandfriendsjv.com/images/homepage_ads/rotator4/exclusive_senior_chickenrice.jpg","http://www.petsandfriendsjv.com/dog_food_exclusive_senior_chickenrice.asp","Exclusive™ Chicken & Rice Senior Formula"],
["http://www.petsandfriendsjv.com/images/homepage_ads/rotator4/naturalbalance_duckpotato.jpg","http://www.petsandfriendsjv.com/dog_food_naturalbalance_duck_sweet_potato_dry.asp","Natural Balance Potato & Duck Formula"],
["http://www.petsandfriendsjv.com/images/homepage_ads/rotator4/naturesvariety_beefmedallions.jpg","http://www.petsandfriendsjv.com/dog_food_naturesvariety_rawbeefpatties.asp","Beef Formula Nature's Variety Raw Frozen Diet for Dogs and Cats"], 
["http://www.petsandfriendsjv.com/images/homepage_ads/rotator4/sciencediet_caninelight.jpg","http://www.petsandfriendsjv.com/dog_food_sciencediet_canine_light.asp","Science Diet Light Adult"]
// no comma at the end of last index 
);
var lastImg="0"; 

function changeimg4()
{   var randNum = getRand();  
document.getElementById("img4").src = arr4[randNum][0]; 
document.getElementById("link4").href = arr4[randNum][1]; 
document.getElementById("img4").title = arr4[randNum][2]; 
setTimeout('changeimg4()',15000);  }  
function getRand () {   var rnum;   
var id=Math.round(Math.random()*(arr4.length-1));   
rnum = id;   if (rnum==lastImg) { rnum = getRand(); }   
lastImg=rnum;   return rnum;  }