var imgs = [
	['images/about_off.jpg', 'images/about_on.jpg', 'about'],
	['images/membership_off.jpg', 'images/membership_on.jpg', 'membership'],
	['images/board_off.jpg', 'images/board_on.jpg', 'board'],
	['images/calendar_off.jpg', 'images/calendar_on.jpg', 'calendar'],
	['images/newsletter_off.jpg', 'images/newsletter_on.jpg', 'newsletter'],
	['images/photos_off.jpg', 'images/photos_on.jpg', 'photos'],
	['images/links_off.jpg', 'images/links_on.jpg', 'links']
] ;

for (var i = 0 ; i < imgs.length ; i++) {
	var obj = new Image () ;
		obj.src = imgs [i][1] ;
}

function chgImg (_num, _state) {
	eval ("document.images." + imgs [_num][2] + ".src = '" + imgs [_num][_state] + "'") ;
}