function Browser() {

	  var ua, s, i;

	  this.isIE    = false;  // Internet Explorer
	  this.isNS    = false;  // Netscape
	  this.version = null;

	  ua = navigator.userAgent;

	  s = "MSIE";
	  if ((i = ua.indexOf(s)) >= 0) {
	    this.isIE = true;
	    this.version = parseFloat(ua.substr(i + s.length));
	    return;
	  }

	  s = "Netscape6/";
	  if ((i = ua.indexOf(s)) >= 0) {
	    this.isNS = true;
	    this.version = parseFloat(ua.substr(i + s.length));
	    return;
	  }

	  // Treat any other "Gecko" browser as NS 6.1.

	  s = "Gecko";
	  if ((i = ua.indexOf(s)) >= 0) {
 	   this.isNS = true;
	    this.version = 6.1;
	    return;
	  }
	}

	var browser = new Browser();

	// Global variable for tracking the currently active button.

	var activeButton = null;

	// Capture mouse clicks on the page so any active button can be
	// deactivated.

	if (browser.isIE)
	  document.onmousedown = pageMousedown;
	if (browser.isNS)
	  document.addEventListener("mousedown", pageMousedown, true);

	function pageMousedown(event) {

	  var el;

	  // If there is no active menu, exit.

	  if (!activeButton)
	    return;

	  // Find the element that was clicked on.

	  if (browser.isIE)
	    el = window.event.srcElement;
	  if (browser.isNS)
	    el = (event.target.className ? event.target : event.target.parentNode);

	  // If the active button was clicked on, exit.

	  if (el == activeButton)
	    return;

	  // If the element clicked on was not a menu button or item, close the
	  // active menu.

	  if (el.className != "menuButton"  && el.className != "menuItem" &&
	      el.className != "menuItemSep" && el.className != "menu")
	    resetButton(activeButton);
	}

	function buttonClick(button, menuName) {

	  // Blur focus from the link to remove that annoying outline.

	  button.blur();

	  // Associate the named menu to this button if not already done.

	  if (!button.menu)
	    button.menu = document.getElementById(menuName);

	  // Reset the currently active button, if any.

	  if (activeButton && activeButton != button)
	    resetButton(activeButton);

	  // Toggle the button's state.

	  if (button.isDepressed)
	    resetButton(button);
	  else
	    depressButton(button);

	  return false;
	}

	function buttonMouseover(button, menuName) {

	  // If any other button menu is active, deactivate it and activate this one.
	  // Note: if this button has no menu, leave the active menu alone.

	  if (activeButton && activeButton != button) {
	    resetButton(activeButton);
	    if (menuName)
	      buttonClick(button, menuName);
	  }
	}

	function depressButton(button) {

	  var w, dw, x, y;

		  // Change the button's style class to make it look like it's depressed.

	  button.className = "menuButtonActive";

	  // For IE, set an explicit width on the first menu item. This will
	  // cause link hovers to work on all the menu's items even when the
	  // cursor is not over the link's text.

	  if (browser.isIE && !button.menu.firstChild.style.width) {
	    w = button.menu.firstChild.offsetWidth;
	    button.menu.firstChild.style.width = w + "px";
	    dw = button.menu.firstChild.offsetWidth - w;
	    w -= dw;
	    button.menu.firstChild.style.width = w + "px";
	  }

	  // Position the associated drop down menu under the button and
	  // show it. Note that the position must be adjusted according to
	  // browser, styling and positioning.

	  x = getPageOffsetLeft(button);
	  y = getPageOffsetTop(button) + button.offsetHeight;
	  if (browser.isIE) {
	    x += 2;
	    y += 2;
	  }
	  if (browser.isNS && browser.version < 6.1)
	    y--;

	  // Position and show the menu.

	  button.menu.style.left = x + "px";
	  button.menu.style.top  = y + "px";
	  button.menu.style.visibility = "visible";

	  // Set button state and let the world know which button is
	  // active.

	  button.isDepressed = true;
	  activeButton = button;
	}

	function resetButton(button) {

	  // Restore the button's style class.

	  button.className = "menuButton";

	  // Hide the button's menu.

	  if (button.menu)
	    button.menu.style.visibility = "hidden";

	  // Set button state and clear active menu global.

	  button.isDepressed = false;
	  activeButton = null;
	}

	function getPageOffsetLeft(el) {

	  // Return the true x coordinate of an element relative to the page.

	  return el.offsetLeft + (el.offsetParent ? getPageOffsetLeft(el.offsetParent) : 0);
	}

	function getPageOffsetTop(el) {

	  // Return the true y coordinate of an element relative to the page.

	  return el.offsetTop + (el.offsetParent ? getPageOffsetTop(el.offsetParent) : 0);
	}