function buttonClick(sender)
{
  if (sender.className == "navbutton button-unpressed")
  {
    sender.className = "navbutton button-pressed";
  }
  else
  if (sender.className == "navbutton button-pressed")
  {
    sender.className = "navbutton button-unpressed";
  }
  
  var leftSideBar = document.getElementById("leftsidebar");
  if (leftSideBar != null)
  {
    var buttonDivs = leftSideBar.getElementsByTagName("DIV");
    for (var i = 0; i < buttonDivs.length; i++)
    {
      var buttonDiv = buttonDivs[i];
      if (buttonDiv != sender)
      {
        buttonDiv.className = "navbutton button-unpressed";
      }
    }
  }
  
  var childLink = sender.firstChild;
  if (childLink.tagName == "A")
  {
    window.location = childLink.href;
  }
}

function selectCurrentPageButton()
{
  var pageIDElements = document.getElementsByName("PageID");
  if (pageIDElements.length > 0)
  {
    var pageIDElement = pageIDElements[0];
    if (pageIDElement.tagName == "META")
    {
      var pageID = pageIDElement.content;
      var pageIDButtonID = "Button" + pageID;
      var pageIDButtonIDElement = document.getElementById(pageIDButtonID);
      if (pageIDButtonIDElement != null)
      {
        pageIDButtonIDElement.className = "navbutton button-pressed";
      }
    }
  }
}