var browserName = navigator.appName;
 var browserVer = parseInt(navigator.appVersion);

function release(num)
{
if (browserVer >= 3){
 if (num == 0) document.but0.src="/images/home.gif"
 if (num == 1) document.but1.src="/images/about.gif"
 if (num == 2) document.but2.src="/images/virtuales.gif"
 if (num == 3) document.but3.src="/images/exhibitions.gif"
 if (num == 4) document.but4.src="/images/order.gif"
 if (num == 5) document.but5.src="/images/gbook.gif"
 if (num == 6) document.but6.src="/images/location.gif"
 if (num == 7) document.but7.src="/images/map.gif"
 if (num == 8) document.but8.src="/images/news.gif"
 if (num == 9) document.but9.src="/images/competitions.gif"
 if (num == 10) document.but10.src="/images/service.gif"
 if (num == 11) document.but11.src="/images/info.gif"
 if (num == 12) document.but12.src="/images/restor.gif"
 if (num == 13) document.but13.src="/images/cofzal.gif"
}}
function press(num)
{
 if (browserVer >= 3){
 if (num == 0) document.but0.src="/images/home_on.gif"
 if (num == 1) document.but1.src="/images/about_on.gif"
 if (num == 2) document.but2.src="/images/virtuales_on.gif"
 if (num == 3) document.but3.src="/images/exhibitions_on.gif"
 if (num == 4) document.but4.src="/images/order_on.gif"
 if (num == 5) document.but5.src="/images/gbook_on.gif"
 if (num == 6) document.but6.src="/images/location_on.gif"
 if (num == 7) document.but7.src="/images/map_on.gif"
 if (num == 8) document.but8.src="/images/news_on.gif"
 if (num == 9) document.but9.src="/images/competitions_on.gif"
if (num == 10) document.but10.src="/images/service_on.gif"
if (num == 11) document.but11.src="/images/info_on.gif"
if (num == 12) document.but12.src="/images/restor_on.gif"
if (num == 13) document.but13.src="/images/cofzal_on.gif"
}}