if (document.images) {

//rollovers
		company = new Image();
		company_down = new Image();
		deliverables = new Image();
		deliverables_down = new Image();
		case_studies = new Image();
		case_studies_down = new Image();
		testimonials = new Image();
		testimonials_down = new Image();
		team = new Image();
		team_down = new Image();
		contact = new Image();
		contact_down = new Image();

//rollovers
		company.src = "_images/nav-company-home-0.gif";
		company_down.src = "_images/nav-company-home-1.gif";
		deliverables.src = "_images/nav-deliverables-0.gif";
		deliverables_down.src = "_images/nav-deliverables-1.gif";
		case_studies.src = "_images/nav-case_studies-0.gif";
		case_studies_down.src = "_images/nav-case_studies-1.gif";
		testimonials.src = "_images/nav-testimonials-0.gif";
		testimonials_down.src = "_images/nav-testimonials-1.gif";
		team.src = "_images/nav-team-0.gif";
		team_down.src = "_images/nav-team-1.gif";
		contact.src = "_images/nav-contact-0.gif";
		contact_down.src = "_images/nav-contact-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")
		}
	}