It appears that if you have one of the Rails 3 beta gems installed, then Sprinkle gets confused when trying to use ActiveSupport’s Dependencies module. This error can be fixed by modifying lib/sprinkle.rb in the gem directory. Add the following line right after require ‘activesupport’ (line 2):
Hopefully the author of Sprinkle will get this bug fixed up soon. An issue on Github has been created.
Update: Github user ahaller has submitted a patch. It sounds like it’s OK to just add the require line even if you are on Rails 2.