can't run: rake gems:install if application.rb depends on initializers

I'm updating an app and wanted to install rspec.

After installing the gem into the system I added:

   config.gem "rspec-rails", :lib => "spec"

to config/environment.rb and ran:

   rake gems:install

However the install does not complete because my initializer is not run.

In my initializer I defined a constant: EXCEPTION_NOTIFIER_CONFIGS_EXISTS that is used in application.rb.

Changing the code in application.rb to this works:

   if defined? EXCEPTION_NOTIFIER_CONFIGS_EXISTS && EXCEPTION_NOTIFIER_CONFIGS_EXISTS
     include ExceptionNotifiable
   end

In general a task that installs a gem shouldn't need to rely on much.

Threads that partially relate to to this are here:

   Initializers aren't run on gem dependency failure
http://groups.google.com/group/rubyonrails-core/browse_thread/thread/bd1ea7763627ed0d

   missing config.gem
http://groups.google.com/group/rubyonrails-core/browse_thread/thread/a9d17c908c0554b1/a333b212d99300ee

However I am not trying to deal with optional gems or continue my application with missing gems -- just trying to install a gem into vendor/gems.