function alternate( id, childTag, offClass, onClass, firstColored )
{
	if( document.getElementsByTagName )
	{
		var myParent = document.getElementById( id );
		var children = new Array(); //myParent.getElementsByTagName( childTag );
		
		for( i = 0; i < myParent.childNodes.length; i++ )
		{
			if( myParent.childNodes[i].tagName == childTag )
			{
				children.push( myParent.childNodes[i] );
			}
		}
		
		var on = false;
		if( firstColored == true ) { on = true; }
		for( i = 0; i < children.length; i++ )
		{
			if( on == false )
			{
				children[i].className = offClass;
				on = true;
			}
			else
			{
				children[i].className = onClass;
				on = false;
			}
		}
	}
}