session / name error

Hi folks.

I am storing some objects in session. Those classes are defined in
/lib/graphalg.rb. So I am requiring it automaticaly. But when
next request, following error is occured:

[usual warning about it being naughty to put objects in the session]

Session contains objects whose class definition isn't available.
Remember to require the classes for all objects kept in the session.
(Original exception: wrong constant name GraphAlg:: [NameError])

I've tried to add require 'GraphAlg' to enviroment.rb, (of course)
doesn't matter.

Unless that's a typo, require 'graphalg' is what you should be typing.