Roll over sub menu

I have a menu with a sub menu I am trying to make it so that when I rollover services the submenu changes to the child pages.
* PRINT
* IDENTITY
* WEB
* SOCIAL MEDIA
* MEDIA PLACEMENT
* MARKETING .

I have it so the submenu changes depending on what page you are on but I would like to add in the rollover. Please check the working menu here. Here is the code I am currently using

<div id="nav">
                         <ul>
		<li class="page_item <?php if (is_home()) echo('current_page_item');?>"></li>
       		 <?php $exclude_pages = get_option('V_pages_to_exclude'); ?>
        <?php wp_list_pages('depth=1&amp;title_li=&amp;exclude=53,33,125,30,1641' . $exclude_pages); ?>
			</ul>

                        <div id="submenu">
                             <ul id="submenu">
		               <li><a title="about" id="aboutnav" href="index.php?page_id=33">ABOUT</a></li>
                               <li><a title="overivew" id="blognav" href="index.php?page_id=30">BLOG</a></li>
                             </ul>
                        </div>

<div id="logopic"><a href="index.php?"><img src="wp-content/themes/wp-sanda/img/logo.png" alt="logo"></a></div>
                       </div>

Please help!