function changeTab(tabId, mainTabId)
{
  var li=document.getElementById(mainTabId);
  var elemclass = document.getElementById(tabId).className;
  var alltabs = document.getElementById(tabId).parentNode.getElementsByTagName('div');
  for( var i = 0; i < alltabs.length; i++ ) 
  {
    if(alltabs[i].className == elemclass)
      alltabs[i].style.display = 'none';
  }
  document.getElementById(tabId).style.display = 'block';  
  var lis = li.parentNode.getElementsByTagName('div');
  for (var i=0;i<lis.length;i++)
  {
    lis[i].className = '';
  }
  li.className = 'current';
}


/*
function rollover()
{
  if(!document.getElementById || !document.createTextNode){return;}
  var n=document.getElementById('toc');
  if(!n){return;}
  var lis=n.getElementsByTagName('li');
  for (var i=0;i<lis.length;i++)
  {
    lis[i].onmouseover=function()
    {
      this.className=this.className?'current':'over';
    }
    lis[i].onmouseout=function()
    {
       this.className=this.className=='current'?'current':'';
    }
  }
}

window.onload=rollover;

*/