// browser test:
	bagent = navigator.appName;
	bversion = parseInt(navigator.appVersion);
	if (bagent == ("Netscape" && bversion >= 3) || bversion >= 4) bversion = 3;
	else bversion = 1;
// preload navigation:
	if (bversion == 3) {
//active images
	about_n = new Image(106, 27);
	about_n.src = "images/sb_about_r.gif";
	prod_n = new Image(106, 26);
	prod_n.src = "images/sb_prod_r.gif";
	tech_n = new Image(106, 26);
	tech_n.src = "images/sb_tech_r.gif";
	price_n = new Image(106, 27);
	price_n.src = "images/sb_price_r.gif";
	cont_n = new Image(106, 27);
	cont_n.src = "images/sb_cont_r.gif";
	press_n = new Image(106, 27);
	press_n.src = "images/sb_press_r.gif";
	present_n = new Image(106, 26);
	present_n.src = "images/sb_present_r.gif";

	mabout_n = new Image(65, 64);
	mabout_n.src = "images/b_about_r.gif";
	mprod_n = new Image(65, 67);
	mprod_n.src = "images/b_prod_r.gif";
	mtech_n = new Image(63, 64);
	mtech_n.src = "images/b_tech_r.gif";
	mprice_n = new Image(51, 63);
	mprice_n.src = "images/b_price_r.gif";
	mcont_n = new Image(57, 64);
	mcont_n.src = "images/b_cont_r.gif";
	mpress_n = new Image(66, 61);
	mpress_n.src = "images/b_press_r.gif";
//unactive images
	about_f = new Image(106, 27);
	about_f.src = "images/sb_about_r_off.gif";
	prod_f = new Image(106, 26);
	prod_f.src = "images/sb_prod_r_off.gif";
	tech_f = new Image(106, 26);
	tech_f.src = "images/sb_tech_r_off.gif";
	price_f = new Image(106, 27);
	price_f.src = "images/sb_price_r_off.gif";
	cont_f = new Image(106, 27);
	cont_f.src = "images/sb_cont_r_off.gif";
	press_f = new Image(106, 27);
	press_f.src = "images/sb_press_r_off.gif";
	present_f = new Image(106, 26);
	present_f.src = "images/sb_present_r_off.gif";

	mabout_f = new Image(65, 64);
	mabout_f.src = "images/b_about_r_off.gif";
	mprod_f = new Image(65, 67);
	mprod_f.src = "images/b_prod_r_off.gif";
	mtech_f = new Image(63, 64);
	mtech_f.src = "images/b_tech_r_off.gif";
	mprice_f = new Image(51, 63);
	mprice_f.src = "images/b_price_r_off.gif";
	mcont_f = new Image(57, 64);
	mcont_f.src = "images/b_cont_r_off.gif";
	mpress_f = new Image(66, 61);
	mpress_f.src = "images/b_press_r_off.gif";
}

function img_swap(targ, img)
{
	if (bversion == 3 && img != '' && targ !='')
	{
	 document[targ].src = eval(img + ".src");
	}
}// enf of img_swap