function select(tab_name) {
	document.getElementById(tab_name).src = "images/" + tab_name + "2.png";
}
function deselect(tab_name) {
	document.getElementById(tab_name).src = "images/" + tab_name + ".png";
}
function preload_images() {
	if (document.images) {
		homepic = new Image(143, 45);
		homepic.src="images/home2.png";
		portfoliopic = new Image(170, 45);
		portfoliopic.src="images/portfolio2.png";
		servicespic = new Image(165, 45);
		servicespic.src="images/services2.png";
		developmentpic = new Image(218, 45);
		developmentpic.src="images/development2.png";
		contactpic = new Image(203, 45);
		contactpic.src="images/contactus2.png";
	}
}