( function()
{
	if (typeof ScriptEngine == "function"){	// IE の場合、DOM の Node オブジェクトなんて存在しないらしい (^_^; 。
		window.Node =
			{ "ELEMENT_NODE"	: 1
			, "TEXT_NODE"		: 3
			};
	}
	var generateSubMenuItemMouseEvent = function( type )
	{
		var display_type =
			type == "over"	? "block" :
			type == "out"	? "none" :
			"none";
		
		return function( e )
		{
			if ( typeof event == "object" )	e = event;
			for ( var i = 0; i < this.childNodes.length; i++ )
			{
				if ( this.childNodes[i].nodeType != Node.ELEMENT_NODE || this.childNodes[i].tagName.toLowerCase() != "ul" )
				//if ( this.childNodes[i].nodeType != 1 || this.childNodes[i].tagName.toLowerCase() != "ul" )
					continue;
				this.childNodes[ i ].style.display = display_type;
			}
		};
	}

	var old_window_onload = window.onload;
	window.onload = function( e )
	{
		if ( typeof event == "object" )	e = event;
		if ( typeof old_window_onload == "function" )
			old_window_onload();
		
		var menu = document.getElementById( "menu" );
		var menu_items = menu.getElementsByTagName( "li" );
		for ( var i = 0; i < menu_items.length; i++ )
		{
			if ( ! menu_items[ i ].className.match( /\bsubmenu\b/ ) )
				continue;
			menu_items[ i ].onmouseover = generateSubMenuItemMouseEvent( "over" );
			menu_items[ i ].onmouseout = generateSubMenuItemMouseEvent( "out" );
		}
	};
} )();