Since MetaWhere is not compatible with Rails 3.1/3.2 and we are now directed to use Squeel instead, and I needed to use CanCan MetaWhere depending functionality, I made this gist that replaces MetaWhere with Squeel in CanCan 1.6.7 . Now one can write:

can :manage, User, :permissions.outer => {:type.matches => 'Manage%'}}

This fixes several issues. Happy coding!