A copy of ApplicationController has been removed from the module tree but is still active! And can’t dup NilClass
If you've been working on Rails 2.3 engines (the new stuff that comes with Rails 2.3 not the old engine plugin) and you start running into either of these errors:
A copy of ApplicationController has been removed from the module tree but is still active!
Or
can’t dup NilClass
Don't go find a new job at McDonald's. Read this article and feel the love again.
In fact if you do any engine or plugin or gem development read that article. It will make you happy again.
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Justin Ball is a software consultant and entrepreneur with a passion for Ruby. He evolved from a C++ and .Net monkey into a python programmer and finally found Ruby. In the rare moments when he isn't writing code, talking about code or measuring his code productivity in profanity per hour, you can find him on his bike in the mountains or on the roads surrounding Cache Valley. 
