function setTab(tab_id, tab_namespace, tab_list, button) {
     var tabs = document.getElementsByName(tab_namespace);
     checkname = false;
     if(!tabs.length) { tabs = document.getElementsByTagName("div"); checkname = true; }
     for(t = 0; t < tabs.length; t++) {
         if(checkname && tabs[t].name != tab_namespace) continue;
         if(tab_id == tabs[t].id) tabs[t].style.display = 'block';
         else tabs[t].style.display = 'none';
     }
     tabsHeader = document.getElementById(tab_list).children;
     for(t = 0; t < tabsHeader.length; t++) {
         if(tabsHeader[t].className != 'clear')
            tabsHeader[t].className = 'item';
     }
     button.className = 'item selected';
 }