AssociationTypeMismatch / Model Caching in development environment

Hi there—

I’m trying to get started with Rails, and I’ve run into this issue and
searched high and low–so hopefully someone can help point me in the
right direction.

I’m having an issue where my model classes seem to be getting cached by
something, and so if I make subsequent requests, I get an
AssociationTypeMismatch error. To be specific, on update is where it
fails, and I get:

ActiveRecord::AssociationTypeMismatch in ArticlesController#update
Category(#2159283720) expected, got Category(#2154954600)

So sometimes this is successful, and the POST requests are identical.

I can change the ‘config.cache_classes = false’ to true in the
config/environments/development to true and i won’t get the error
anymore, but then I have to reload the server every time I make a

I read that plugins could be caching it since they don’t reload for
request, but I don’t think I’m using any plugins, so I’m guessing that
isn’t it.

I can’t figure out where to look next and would appreciate any help you
can offer.

I’m running Ruby 1.9.2p0 and Rails 3.0.1 on OS X 10.6.4. You can
download the code that I’m trying to work on at (I’m trying to work
through this Apress book). When you load up the page, you need to log
in to edit, and the login is ‘[email protected]’ : ‘guessit’.

Any pointers or ideas?