rails/activerecord-session_store — pull request #7 by johnthethird (2013-02-15 21:43:39+00:00)
Title: Threading issue when redefining find_by_session_id

Running under JRuby exposes a problem with the way method redefinition happens with the `find_by_session_id` method. This patch wraps that with an exclusive block ensuring that one thread doesnt remove a method from underneath another.