function fadeOut(elementID, fade_duration)
{
	_fadeOut(100, elementID, fade_duration, false);
}

function fadeOutAndHide(elementID, fade_duration)
{
	_fadeOut(100, elementID, fade_duration, true);
}

function _fadeOut(opacity, elementID, fade_duration, hideAfterFading)
{
	document.getElementById(elementID).style.opacity = opacity / 100;
	document.getElementById(elementID).style.filter = "alpha(opacity=" + opacity + ")";

	if (opacity > 0)
		setTimeout("_fadeOut(" + (opacity - 2) + ", '" + elementID + "', " + fade_duration + ", " + hideAfterFading + ")", fade_duration / 100);
	else if (opacity == 0 && hideAfterFading)
		document.getElementById(elementID).style.display = "none";
}

function fadeIn(elementID, fade_duration)
{
	_fadeIn(0, elementID, fade_duration);
}

function _fadeIn(opacity, elementID, fade_duration)
{
	document.getElementById(elementID).style.opacity = opacity / 100;
	document.getElementById(elementID).style.filter = "alpha(opacity=" + opacity + ")";
	document.getElementById(elementID).style.display = "block";

	if (opacity < 100)
		setTimeout("_fadeIn(" + (opacity + 2) + ", '" + elementID + "', " + fade_duration + ")", fade_duration / 100);
}