var but1n = new Image()
but1n.src = "images/but-back.gif"
var but1a = new Image()
but1a.src = "images/navb1.gif"
var but2n = new Image()
but2n.src = "images/but_subscriber_on.gif"
var but2a = new Image()
but2a.src = "images/but_subscriber_off.gif"
var but3n = new Image()
but3n.src = "images/but_store_on.gif"
var but3a = new Image()
but3a.src = "images/but_store_off.gif"
var but4n = new Image()
but4n.src = "images/but_club_on.gif"
var but4a = new Image()
but4a.src = "images/but_club_off.gif"
var but5n = new Image()
but5n.src = "images/but_education_on.gif"
var but5a = new Image()
but5a.src = "images/but_education_off.gif"
var but6n = new Image()
but6n.src = "images/but_contact_on.gif"
var but6a = new Image()
but6a.src = "images/but_contact_off.gif"

function act(imgName) {
document[imgName].src = eval(imgName + 'n.src')
}
function inact(imgName) {
document[imgName].src = eval(imgName + 'a.src')
}