if (document.images) {

//rollovers
		profile = new Image();
		profile_down = new Image();
		capabilities = new Image();
		capabilities_down = new Image();
		portfolio = new Image();
		portfolio_down = new Image();
		methodology = new Image();
		methodology_down = new Image();
		contact = new Image();
		contact_down = new Image();
		laboratory = new Image();
		laboratory_down = new Image();

		profile.src = "images/btn-home-profile-0.gif";
		profile_down.src = "images/btn-home-profile-1.gif";
		capabilities.src = "images/btn-home-capabilities-0.gif";
		capabilities_down.src = "images/btn-home-capabilities-1.gif";
		portfolio.src = "images/btn-home-portfolio-0.gif";
		portfolio_down.src = "images/btn-home-portfolio-1.gif";
		methodology.src = "images/btn-home-methodology-0.gif";
		methodology_down.src = "images/btn-home-methodology-1.gif";
		contact.src = "images/btn-home-contact-0.gif";
		contact_down.src = "images/btn-home-contact-1.gif";
		laboratory.src = "images/btn-home-laboratory-0.gif";
		laboratory_down.src = "images/btn-home-laboratory-1.gif";

}

function buttonOn(imageName) {
	if (document.images) {
		document[imageName].src = eval(imageName+"_down.src")
		}
	}

function buttonOff(imageName) {
	if (document.images) {
		document[imageName].src = eval(imageName+".src")
		}
	}