after executing "rake alchemy:db:seed" :
"Seeding your database
Can't mass-assign protected attributes: name, language_code, frontpage_name, page_layout, public, default
Tasks: TOP => alchemy:db:seed"
I was able to reproduce this issue with a new rails app and 2.2.rc1.
However this issue does not appear with 2.2.rc4 (master-branch).
I'll have a look at the commits that has been made meanwhile. As long as this has not been fixed you can use the master-branch.
Thanks for reporting this!
Fixed with newest commits in master.