fixedMenuId = 'fixeddiv';

var fixedMenu = 
{
    hasInner: typeof(window.innerWidth) == 'number',
    hasElement: document.documentElement != null
       && document.documentElement.clientWidth,

    menu: document.getElementById
        ? document.getElementById(fixedMenuId)
        : document.all
          ? document.all[fixedMenuId]
          : document.layers[fixedMenuId]
};

fixedMenu.computeShifts = function()
{
    fixedMenu.shiftX = fixedMenu.hasInner
        ? pageXOffset
        : fixedMenu.hasElement
          ? document.documentElement.scrollLeft
          : document.body.scrollLeft;
    if (fixedMenu.targetLeft > 0)
        fixedMenu.shiftX += fixedMenu.targetLeft;
    else
    {
        fixedMenu.shiftX += 
            (fixedMenu.hasElement
              ? document.documentElement.clientWidth
              : fixedMenu.hasInner
                ? window.innerWidth - 20
                : document.body.clientWidth)
            - fixedMenu.targetRight
            - fixedMenu.menu.offsetWidth;
    }

    fixedMenu.shiftY = fixedMenu.hasInner
        ? pageYOffset
        : fixedMenu.hasElement
          ? document.documentElement.scrollTop
          : document.body.scrollTop;
    if (fixedMenu.targetTop > 0)
        fixedMenu.shiftY += fixedMenu.targetTop;
    else
    {
        fixedMenu.shiftY += 
            (fixedMenu.hasElement
            ? document.documentElement.clientHeight
            : fixedMenu.hasInner
              ? window.innerHeight - 20
              : document.body.clientHeight)
            - fixedMenu.targetBottom
            - fixedMenu.menu.offsetHeight;
    }
};

fixedMenu.moveMenu = function()
{
    fixedMenu.computeShifts();

    if (fixedMenu.currentX != fixedMenu.shiftX
        || fixedMenu.currentY != fixedMenu.shiftY)
    {
        fixedMenu.currentX = fixedMenu.shiftX;
        fixedMenu.currentY = fixedMenu.shiftY;

        if (document.layers)
        {
            fixedMenu.menu.left = fixedMenu.currentX;
            fixedMenu.menu.top = fixedMenu.currentY;
        }
        else
        {
            fixedMenu.menu.style.left = fixedMenu.currentX + 'px';
            fixedMenu.menu.style.top = fixedMenu.currentY + 'px';
        }
    }

    fixedMenu.menu.style.right = '';
    fixedMenu.menu.style.bottom = '';
};

fixedMenu.floatMenu = function()
{
	if (fixedMenu.menu.offsetHeight < window.innerHeight) 
	{
	    fixedMenu.moveMenu();
    	setTimeout('fixedMenu.floatMenu()', 20);
	}
};

// addEvent designed by Aaron Moore
fixedMenu.addEvent = function(element, listener, handler)
{
    if(typeof element[listener] != 'function' || 
       typeof element[listener + '_num'] == 'undefined')
    {
        element[listener + '_num'] = 0;
        if (typeof element[listener] == 'function')
        {
            element[listener + 0] = element[listener];
            element[listener + '_num']++;
        }
        element[listener] = function(e)
        {
            var r = true;
            e = (e) ? e : window.event;
            for(var i = 0; i < element[listener + '_num']; i++)
                if(element[listener + i](e) === false)
                    r = false;
            return r;
        }
    }

    //if handler is not already stored, assign it
    for(var i = 0; i < element[listener + '_num']; i++)
        if(element[listener + i] == handler)
            return;
    element[listener + element[listener + '_num']] = handler;
    element[listener + '_num']++;
};

fixedMenu.supportsFixed = function()
{
    var testDiv = document.createElement("div");
    testDiv.id = "testingPositionFixed";
    testDiv.style.position = "fixed";
    testDiv.style.top = "0px";
    testDiv.style.right = "0px";
    document.body.appendChild(testDiv);
    var offset = 1;
    if (typeof testDiv.offsetTop == "number"
        && testDiv.offsetTop != null 
        && testDiv.offsetTop != "undefined")
    {
        offset = parseInt(testDiv.offsetTop);
    }
    if (offset == 0)
    {
        return true;
    }

    return false;
};

var theWidth, theHeight;
// Window dimensions:
if (window.innerWidth) {
theWidth=window.innerWidth;
}
else if (document.documentElement && document.documentElement.clientWidth) {
theWidth=document.documentElement.clientWidth;
}
else if (document.body) {
theWidth=document.body.clientWidth;
}
if (window.innerHeight) {
theHeight=window.innerHeight;
}
else if (document.documentElement && document.documentElement.clientHeight) {
theHeight=document.documentElement.clientHeight;
}
else if (document.body) {
theHeight=document.body.clientHeight;
}

fixedMenu.init = function()
{
	if (document.getElementById(fixedMenuId).clientHeight > theHeight || fixedMenu.menu.offsetHeight > document.getElementById("right_content").clientHeight) 
	{
		ResetFixedMenu ();
	}
	else
	{
		if (fixedMenu.supportsFixed())
			fixedMenu.menu.style.position = "fixed";
		else
		{
			var ob = 
				document.layers 
				? fixedMenu.menu 
				: fixedMenu.menu.style;
	
			fixedMenu.targetLeft = parseInt(ob.left);
			fixedMenu.targetTop = parseInt(ob.top);
			fixedMenu.targetRight = parseInt(ob.right);
			fixedMenu.targetBottom = parseInt(ob.bottom);
	
			if (document.layers)
			{
				menu.left = 0;
				menu.top = 0;
			}
			fixedMenu.addEvent(window, 'onscroll', fixedMenu.moveMenu);
			fixedMenu.floatMenu();
		} 
			
	}
};


function ResetFixedMenu ()
{
	if (window.innerHeight) {
		theHeight=window.innerHeight;
	}
	else if (document.documentElement && document.documentElement.clientHeight) {
		theHeight=document.documentElement.clientHeight;
	}
	else if (document.body) {
		theHeight=document.body.clientHeight;
	}	


	if (document.getElementById(fixedMenuId).clientHeight > theHeight  || document.getElementById(fixedMenuId).clientHeight > document.getElementById("right_content").clientHeight) 
	{
		document.getElementById(fixedMenuId).style.position  = "static";	
	}
	else
	{
		document.getElementById(fixedMenuId).style.position = "fixed";
	}
}

fixedMenu.addEvent(window, 'onload', fixedMenu.init);