var tab = {
init: function(init_num)
      {
          var tabs = this.setup.tabs;
          var pages = this.setup.pages;

          for(i=0; i<pages.length; i++) {
              if(i !== init_num) pages[i].style.display = 'none';
              tabs[i].onclick = function(){ tab.showpage(this); return false; };
          }
      },
showpage: function(obj)
          {
              var tabs = this.setup.tabs;
              var pages = this.setup.pages;
              var num;

              for(num=0; num<tabs.length; num++) {
                  if(tabs[num] === obj) break;
              }

              for(var i=0; i<pages.length; i++) {
                  if(i == num) {
                      pages[num].style.display = 'block';
                      tabs[num].className = tabs[num].className + ' ' + tabs[num].className + '_selected';
                  }
                  else{
                      pages[i].style.display = 'none';
                      var tmpClass = tabs[i].className.split(" ");
                      tabs[i].className = tmpClass[0];
                  }
              }
          }
}