i have the same problem.
in the admin login it says "u are redirectet" and then go back to login. the same with the user login.
i am using apache 2.2.4 and php 5.2.0.
for the background, i transerfed the site to a new hoster. imported the DB using phpmyadmin, changed the config.php and it just worked fine. i can surf trough the whole page, but cannt log in. other users can't log in as well. bevor the tranver it all goes well.
i supose it could be the directory rights in apache, because i dont have so much knowledge about apache ...
here are my directoy settings:
AllowOverride None
Options None
Order allow,deny
Allow from all
anyone any ideas?