When I change the week to start on Sunday in the General options, the output list on my archives page shows the proper dates for those weeks (Sunday-Saturday):
http://www.jordanisyourhomeboy.com/archives.php
However, when you click on a link, it still displays the posts from that week from Monday-Sunday. For instance, when you click on "July 9, 2006–July 15, 2006", it shows posts from July 10, 2006-July 16, 2006. Is there another setting I have to fix to make this work properly, or is it a bug?