Demonstration of warning messages that *still* occur after adding heroku gem to a Rails 3 app

gistfile1.sh

$ gem list heroku

*** LOCAL GEMS ***

heroku (1.13.6)

$ rails g
/Users/ed_ruder/.rvm/gems/ruby-1.8.7-p299@rails3/gems/json-1.4.6/lib/json/common.rb:65: warning: already initialized constant State
/Users/ed_ruder/.rvm/gems/ruby-1.8.7-p299@rails3/gems/json-1.4.6/lib/json/common.rb:66: warning: already initialized constant SAFE_STATE_PROTOTYPE
/Users/ed_ruder/.rvm/gems/ruby-1.8.7-p299@rails3/gems/json-1.4.6/lib/json/common.rb:67: warning: already initialized constant FAST_STATE_PROTOTYPE
/Users/ed_ruder/.rvm/gems/ruby-1.8.7-p299@rails3/gems/json-1.4.6/lib/json/common.rb:74: warning: already initialized constant PRETTY_STATE_PROTOTYPE
/Users/ed_ruder/.rvm/gems/ruby-1.8.7-p299@rails3/gems/json-1.4.6/lib/json/ext.rb:14: warning: already initialized constant JSON_LOADED
Usage: rails generate GENERATOR [args] [options]

General options:
  -h, [--help]     # Print generator's options and usage
  -p, [--pretend]  # Run but do not make any changes
  -f, [--force]    # Overwrite files that already exist
  -s, [--skip]     # Skip files that already exist
  -q, [--quiet]    # Suppress status output

...

$ gem uninstall heroku
Remove executables:
	heroku

in addition to the gem? [Yn]  y
Removing heroku
Successfully uninstalled heroku-1.13.6

$ rails g
Usage: rails generate GENERATOR [args] [options]

General options:
  -h, [--help]     # Print generator's options and usage
  -p, [--pretend]  # Run but do not make any changes
  -f, [--force]    # Overwrite files that already exist
  -s, [--skip]     # Skip files that already exist
  -q, [--quiet]    # Suppress status output

...