document.btn_img=new Array();

function preload()
{
var d=document;
if (d.images)
{
    var i,j=d.btn_img.length,a=preload.arguments;
	for(i=0; i<a.length; i++)
    if (a[i].indexOf("#")!=0)
	{
		d.btn_img[j]=new Image;
		d.btn_img[j++].src=a[i];
	}
}
}

function btn_on(obj,name)
{
obj.src=name;
}

function btn_off(obj,name)
{
if (obj.id!='a') obj.src=name;
}