<!--
/*
 * Link highlighting code.  The links in question here are all images.
 * Highlighting, or activating, a link means loading a highlighted image in
 * the place of a link image.  Deactivating a link means reloading the normal,
 * unhighlited link image.  If the browser is not supported, then activation
 * and deactivation will do nothing.
 */

/*
 * Detect whether or not browser is supported.
 */
browserName = navigator.appName;
browserVersion = parseInt(navigator.appVersion);
if ((browserName == "Netscape"                    && browserVersion >= 3) || 
    (browserName == "Microsoft Internet Explorer" && browserVersion >= 4))
	browserSupported = "yes"; 
else
	browserSupported = "no";
/*
 * Preload all active and inactive images.
 */
if (browserSupported == "yes") {
	hb0ImgAct   = new Image();
	hb1ImgAct   = new Image();
	hb2ImgAct   = new Image();
	hb0ImgAct.src   = "images/4_05.gif";
	hb1ImgAct.src   = "images/4_06.gif";
	hb2ImgAct.src   = "images/4_07.gif";
	hb0ImgInact   = new Image();
	hb1ImgInact   = new Image();
	hb2ImgInact   = new Image();
	hb0ImgInact.src   = "images/4h_05.gif";
	hb1ImgInact.src   = "images/4h_06.gif";
	hb2ImgInact.src   = "images/4h_07.gif";

}
/*
 * Functions to activate header buttons.
 */
function hb0Act() {
	if (browserSupported == "yes") {
		document["hb0"].src  = hb0ImgAct.src;		
	}
}
function hb1Act() {
	if (browserSupported == "yes") {
		document["hb1"].src  = hb1ImgAct.src;
	}
}
function hb2Act() {
	if (browserSupported == "yes") {
		document["hb2"].src   = hb2ImgAct.src;
	}
}
/*
 * Functions to deactivate header buttons.
 */
function hb0Inact() {
	if (browserSupported == "yes") {
		document["hb0"].src  = hb0ImgInact.src;
	}
}
function hb1Inact() {
	if (browserSupported == "yes") {
		document["hb1"].src  = hb1ImgInact.src;
	}
}
function hb2Inact() {
	if (browserSupported == "yes") {
		document["hb2"].src  = hb2ImgInact.src;
	}
}
//-->