function preloadImages() 
{ 
pic1 = new Image();
pic1.src = "gfx/menu/but1_2.jpg";
pic2 = new Image();
pic2.src = "gfx/menu/but2_2.jpg";
pic3 = new Image();
pic3.src = "gfx/menu/but3_2.jpg";


}

function changeImage(id, imgName)
{

theImage = document.getElementById(id);

theImage.src='gfx/menu/' + imgName;

}


function load_header()
{
var randomnumber= Math.floor(Math.random()*10); //generate a number 0-9


document.getElementById("header2").style.background = "center no-repeat url(gfx/headers/" + randomnumber + ".jpg)";
}