Oscommerce / PHP Expert for Oscommerce category design

Please read all our requirements below before responding. Please only reply if you can definitely do it. Everyone who uses oscommerce is familiar with the standard way Oscommerce displays the category links. We have two main sections of our site. Womens and Mens. We would like the way categories to display the same as the web-site [login to view URL] (please see attached file) As you can see on the [login to view URL] site the two main category options (Men and Women) always remain at the top and the sub categories load beneath them. Please only bid if you will be able to create a script that will work the same as how [login to view URL] displays its categories.