// Detect if browser is Netscape 3 + or IE 4 +.
	var br
	bName = navigator.appName;
	bVer = parseInt(navigator.appVersion);
	    if ((bName == "Netscape" && bVer >= 3) || (bName == "Microsoft Internet Explorer" && bVer >= 4))
	    {
	    	br = "n3"; 
	    }
	    else
	    {
	    	br = "n2";
	    }

// Create image objects, preload all active and inactive images.
if (br == "n3") {
	// images for business challenge switch thingy
	portfolio_On =new Image();
	portfolio_On.src = "imgs/nav_portfolios_on.gif" ;

	portfolio_Off = new Image();
	portfolio_Off.src = "imgs/nav_portfolios_off.gif" ;

	bio_On = new Image();
	bio_On.src = "imgs/nav_bio_on.gif" ;

	bio_Off = new Image();
	bio_Off.src = "imgs/nav_bio_off.gif" ;
	
	clients_On = new Image();
	clients_On.src = "imgs/nav_clients_on.gif" ;

	clients_Off = new Image();
	clients_Off.src = "imgs/nav_clients_off.gif" ;

	booksandprints_On = new Image();
	booksandprints_On.src = "imgs/nav_booksandprints_on.gif" ;
	
	booksandprints_Off = new Image();
	booksandprints_Off.src = "imgs/nav_booksandprints_off.gif" ;
	
	exhibitions_On = new Image();
	exhibitions_On.src = "imgs/nav_exhibitions_on.gif" ;
	
	exhibitions_Off = new Image();
	exhibitions_Off.src = "imgs/nav_exhibitions_off.gif" ;

	contact_On = new Image();
	contact_On.src = "imgs/nav_contact_on.gif" ;

	contact_Off = new Image();
	contact_Off.src = "imgs/nav_contact_off.gif" ;
}


function navImg() {
	//swaps the appropriate navigation image depending on the page variable
	if (br == "n3") {
		switch (page) {
			case "portfolio":
				document.images.portfolio.src = "imgs/nav_portfolios_on.gif";
				portfolio_Off.src = "imgs/nav_portfolios_on.gif";
				switchAll();
			break;
	
			case "bio":
				document.images.bio.src = "imgs/nav_bio_on.gif";
				bio_Off.src = "imgs/nav_bio_on.gif";
				switchAll();
			break;			
			
			case "clients":
				document.images.clients.src = "imgs/nav_clients_on.gif";
				clients_Off.src = "imgs/nav_clients_on.gif";
				switchAll();
			break;
		
			case "booksandprints":
				document.images.booksandprints.src = "imgs/nav_booksandprints_on.gif";
				booksandprints_Off.src = "imgs/nav_booksandprints_on.gif";
				switchAll();
			break;

	
			case "exhibitions":
				document.images.exhibitions.src = "imgs/nav_exhibitions_on.gif";
				exhibitions_Off.src = "imgs/nav_exhibitions_on.gif";
				switchAll();
			break;

			case "contact":
				document.images.contact.src = "imgs/nav_contact_on.gif";
				contact_Off.src = "imgs/nav_contact_on.gif";
				switchAll();
			break;
			
			case "home":
				document.images.portfolio.src = "imgs/nav_portfolios_off.gif";
				portfolio_Off.src = "imgs/nav_portfolios_off.gif";
				switchAll();
			}

		}		
	}
// image swapping function
function imgOn (iname) {
	if (br == "n3") {
		document[iname].src = eval(iname + "_On.src");
	}
}
function imgOff (iname){
	if (br == "n3") {
		document[iname].src = eval(iname + "_Off.src");
	}
}

function switchAll() {
// fix for Mac IE 5 		
			imgOff('portfolio');
			imgOff('bio');			
			imgOff('clients');
			imgOff('booksandprints');			
			imgOff('exhibitions');		
			imgOff('contact');
// end fix
}
// -->