Hello, I use up to date mongoid 4.0.0 master.

I tried using the store_in macro.

It seems to work fine on base classes:

avril14th@avril14th-ubuntu:~/src/white/trunk$ rails c test
Loading test environment (Rails 4.0.2)
2.1.0 :001 > class Beta
2.1.0 :002?> include Mongoid::Document
2.1.0 :003?> store_in :collection => 'beats'
2.1.0 :004?> end
=> {:collection=>"beats", :session=>:default, :database=>#<Proc:0x0000000163d6b0@/home/avril14th/.rvm/gems/ruby-2.1.0/bundler/gems/mongoid-5b0f031992cb/lib/mongoid/sessions/storage_options.rb:78 (lambda)>}
2.1.0 :006 > b = Beta.new
=> #<Beta _id: 5304cd126176726c15000000, >

now, using it on a derived class fails:

2.1.0 :007 > class R < Beta
2.1.0 :008?> store_in :collection => 'yeah'
2.1.0 :009?> end
Mongoid::Errors::InvalidStorageOptions:
Problem:
Invalid options passed to R.store_in: {:collection=>"yeah"}.
Summary:
The :store_in macro takes only a hash of parameters with the keys :database, :collection, or :session.
Resolution:
Change the options passed to store_in to match the documented API, and ensure all keys in the options hash are symbols.

Is this a natural / desired behavior?