Home Page button on Nav Menu too low.

For some reason the HOME link in the Nav menu is below the rest of the links in the Nav Menu. It seems to do this only in Firefox. It is good in Safari. I haven’t tried it in internet explorer.

Any ideas?

Here is the code from my Header.php file

<div class="navcontainer">
					<?php
                    if(function_exists('wp_nav_menu')) {
                        wp_nav_menu( 'depth=1&theme_location=menu_2&menu_id=nav&container=&fallback_cb=menu_2_default');
                    } else {
                        menu_2_default();
                    }

                    function menu_2_default()
                    {
                        ?>
                        <ul id="nav">
                            <li <?php if(is_home()) { echo ' class="current-cat" '; } ?>><a href="<?php bloginfo('url'); ?>">Home</a></li>
    						<?php wp_list_categories('depth=1&hide_empty=0&orderby=name&order=ASC&title_li=' ); ?>
    					</ul>
                        <?php
                    }
                ?>

				</div>