var ImageArray = new Array('templates/1.jpg','templates/2.jpg');

function RotateImages( Start )
{
  	if(Start >= ImageArray.length)
 		Start=0;
 	var b = document.getElementById('bannerIMG')
 	b.src = ImageArray[Start];
 	window.setTimeout("RotateImages("+(Start+1)+")",4000);
}

RotateImages(0);