IE7 not rendering HTML generated by wp_page_menu

Hello Folks,

I’m just doing some cross browser testing now that I’m launching a site I’ve been building for a friend’s small business. I’m on a Mac, but have been using sites such as IE NetRenderer and BrowserShots to get screens of how the site looks in different browsers on Windows.

The site is: http://www.icecreamvanhireyorkshire.co.uk. The screenshot I’m basing this on is here: http://www.icecreamvanhireyorkshire.co.uk/misc/IE7-05-06-2011.png

The code I have in my header is:

<div id="wrapper" class="hfeed">
	<div id="header">
	   <div id="blog-title">
<span><a href="<?php bloginfo( 'url' ) ?>/" title="Happy Sundaes - Ice Cream Van Hire Yorkshire" rel="home">
<img src="<?php bloginfo("template_url"); ?>/img/logo.png" alt="Ice Cream Van Hire Yorkshire" /></a></span>
            </div><!-- #blog-title -->
            <div id="tabs">
              <?php wp_page_menu( 'sort_column=menu_order&exclude=286,292' ); ?>
            </div><!-- #tabs -->
    </div><!-- #header -->
        <div class="seperator"></div>
	<div id="main">

The id’s ‘tabs’ and ‘menu’ don’t have any CSS associated with them, and the CSS for the list is:

#tabs ul {
    display: inline;
    float: right;
    list-style: none outside none;
    margin: 0;
    padding: 0;
}
#tabs li {
    display: inline;
    margin: 0;
}

I have a feeling something obvious may be staring me in the face, but then again I’ve only seen the issue replicated in IE7! IE8 and 9 are both rendering that menu perfectly!

Any advice much appreciated!

Cheers,
Dave