just for the record...
I logged in with my drupal.org id which automatically created a login for this site. The login was created while attempting to post a reply to another post. After automatic creation and login, I was redirected to the post, but I received following warnings:
warning: array_keys() [function.array-keys]: The first argument should be an array in /var/www/vhosts/www.ubercart.org/modules/user/user.module on line 378.
warning: array_fill() [function.array-fill]: Number of elements must be positive in /var/www/vhosts/www.ubercart.org/modules/user/user.module on line 379.
warning: implode() [function.implode]: Bad arguments. in /var/www/vhosts/www.ubercart.org/modules/user/user.module on line 379.
user warning: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ')' at line 1 query: SELECT DISTINCT(p.perm) FROM role r INNER JOIN permission p ON p.rid = r.rid WHERE r.rid IN () in /var/www/vhosts/www.ubercart.org/includes/database.mysql.inc on line 172.so I'm not sure something went wrong, just telling so that you know 
http://www.ubercart.org/forum/bug_reports/3099/uc_login_error
http://www.ubercart.org/forum/bug_reports/3090/errors_whenlogging_uberca...
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