nav_about_off = new Image();
nav_about_off.src = "images/about_off.gif";
nav_about_on = new Image();
nav_about_on.src = "images/about_on.gif";

nav_services_off = new Image();
nav_services_off.src = "images/services_off.gif";
nav_services_on = new Image();
nav_services_on.src = "images/services_on.gif";

nav_feature_off = new Image();
nav_feature_off.src = "images/feature_off.gif";
nav_feature_on = new Image();
nav_feature_on.src = "images/feature_on.gif";

nav_contact_off = new Image();
nav_contact_off.src = "images/contact_off.gif";
nav_contact_on = new Image();
nav_contact_on.src = "images/contact_on.gif";


function imageon(imagename) {
	imgOn = eval(imagename + "_on.src");
	document[imagename].src = imgOn;
}

function imageoff(imagename) {
	imgOff = eval(imagename + "_off.src");
	document[imagename].src = imgOff;
}