Current Page Item adding extra space in IE7!!

My built-from-scratch WordPress site has one little problem, but only in IE7…

I’ve added current page item php functionality to the navigation bar, and this is creating about 15 pixels extra space to the left of the start of the navigation bar (not between the individual buttons). This extra space breaks the navigation div.

I’ve honed down the problem to the current page item functionality. Here is the navigation code:

<ul>
<li class="page_item <?php if (is_front_page()) { ?>current_page_item<?php }?>"></li>
<?php wp_list_pages('title_li=&depth=2&sort_column=menu_order') ?>
</ul>

However if I remove the first line:
<li class="page_item <?php if (is_front_page()) { ?>current_page_item<?php }?>"></li>

…everything is fine! So that must be it, but I don’t know what to do.

And again, this seems to only be in IE7. Anyone have any experience at all with this?