404 error for /admin/groups with gitlab 5.0

Created by: ph03

Hi! I have gitlab 5.0 running and everything is fine except when I try to access /admin/groups:

Started GET "/admin/groups" for 127.0.0.1 at 2013-04-13 01:25:56 +0200
Processing by Admin::GroupsController#index as HTML
  Rendered admin/groups/index.html.haml within layouts/admin (16.3ms)
Completed 500 Internal Server Error in 24ms

ActionController::RoutingError (No route matches {:action=>"show", :controller=>"admin/users", :id=>nil}):
  app/views/admin/groups/index.html.haml:33:in `block in _app_views_admin_groups_index_html_haml__1270575898731690568_39241620'
  app/views/admin/groups/index.html.haml:25:in `_app_views_admin_groups_index_html_haml__1270575898731690568_39241620'

I get a 404 error by nginx here.

Is this a known problem / how can I fix it? The id=>nil is suspicious to me...