var DOM = (document.getElementById)?true:false;
		var IE = (document.all)?true:false;
		var IE4 = (IE && !DOM);
		var NS4 = (document.layers)?true:false;
		var NS = (navigator.appName.toLowerCase().indexOf("netscape") != -1)?true:false;
			
		function getImgRef(imgId) {
			var obj = null;
			if (DOM || IE4)
				var obj = getObjRef(imgId);
			else if (NS4)
				var obj = eval("document." + imgId);
			return (obj);
		}
	
		function getObjRef(objId) {
			var obj = null;
			if (DOM)
				var obj = document.getElementById(objId);
			else if (IE4)
				var obj = document.all[objId];
			else if (NS4)
				var obj = document.layers[objId];
			return (obj);
		}
		
		function createImage(sPath) {
			var oImg = new Image();
			oImg.src = sPath;
			return (oImg);
		}
		
		NAV = [
			["nav_history",			createImage("/pics/front/link-history.gif"),			createImage("/pics/front/link-history-a.gif")],
			["nav_capabilities",	createImage("/pics/front/link-capabilities.gif"),		createImage("/pics/front/link-capabilities-a.gif")],
			["nav_decorative",		createImage("/pics/front/link-decorative.gif"),		createImage("/pics/front/link-decorative-a.gif")],
			["nav_municipal",		createImage("/pics/front/link-municipal.gif"),		createImage("/pics/front/link-municipal-a.gif")],
			["nav_contact",			createImage("/pics/front/link-contact.gif"),			createImage("/pics/front/link-contact-a.gif")],
			["nav_request",			createImage("/pics/front/link-request.gif"),			createImage("/pics/front/link-request-a.gif")]
		];

		function navOver(navId, bOver) {
			if (DOM || IE4 || NS4) {
				for (n=0;n<NAV.length;n++) {
					if (navId.toLowerCase() == NAV[n][0].toLowerCase()) {
						var oImg = getImgRef(navId);
						if (bOver)
							oImg.src = NAV[n][2].src;
						else
							oImg.src = NAV[n][1].src;
						break;
					}
				}
			}
		}