// preload images
var a = new Image();
a.src = "/pics/nav_r1_c1_on.gif";
var b = new Image();
b.src = "/pics/nav_r2_c1_on.gif";
var c = new Image();
c.src = "/pics/nav_r3_c1_on.gif";
var d = new Image();
d.src = "/pics/nav_r4_c1_on.gif";
var e = new Image();
e.src = "/pics/nav_r5_c1_on.gif";
var f = new Image();
f.src = "/pics/nav_r6_c1_on.gif";
var g = new Image();
g.src = "/pics/nav_r7_c1_on.gif";
var h = new Image();
h.src = "/pics/nav_r8_c1_on.gif";
var i = new Image();
i.src = "/pics/nav_r9_c1_on.gif";

// set a image to stay on here
var imageon = '';


// rollover routines
function imageOn (imagename) {
	document[imagename].src = "/pics/"+imagename+"_on.gif";
}
function imageOff (imagename) {
	document[imagename].src = "/pics/"+imagename+".gif";

	if (imageon) {
		document[imageon].src = "/pics/"+imageon+"_on.gif";
	}
}

function alwaysOn () {
	// turn on appropriate image
	if (imageon) {
		document[imageon].src = "/pics/"+imageon+"_on.gif";
	}
}