WordPress MU

Hi. I am using the most recent version of wordpress. Our blooging site has over 500 themes on it, and therefore we have a small problem. Users may want to look through a large number of the themes but it takes a long time because the theme options page in control panel only shows 15 themes. Does anybody know a way of making that theme selection page display, say, 85 themes?
Thanks in advance.
Sam

wp-admin/themes.php

Edit the line (line 95?):

$per_page = 15;

I use a mu-plugin to replace/redeliver the theme selection page altogether:

http://wpmudevorg.wordpress.com/project/Rollover-Themes-List