I have multiple blogs for past more than a year using WPMU. Recently when I upgraded to 3.1, I noticed that the super admin menu is replaced by network admin and when I tried to access the network admin, I am getting redirect loop basically for all URLs starting with /wp-admin/network. I have tried all options like disabling all plugins, removing all plugins, reinstalling fresh copy of 3.1 and changing the config file, reinstalling plugins, installing plugins to block canonical redirects. But so far nothing has worked. The blogs are working OK (have not done extensive testing) but things look good. Only in case of wp-admin/network/* I am getting the redirect loop. Can some one help? Thanks in advance.