Ruby Gems returns "command not found" - ruby

Question

Ubuntu 9.10
Just installed newgem
gem install newgem
and when i try
newgem new_project
I get
adam#adam-ubuntu:~$ newgem newproject
newgem: command not found
Ive checked my path via echo $PATH
adam#adam-ubuntu:~$ echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/home/adam/.gem
and my gem enviroment
adam#adam-ubuntu:~$ gem environment
RubyGems Environment:
- RUBYGEMS VERSION: 1.3.6
- RUBY VERSION: 1.8.7 (2009-06-12 patchlevel 174) [x86_64-linux]
- INSTALLATION DIRECTORY: /usr/lib/ruby/gems/1.8
- RUBY EXECUTABLE: /usr/bin/ruby1.8
- EXECUTABLE DIRECTORY: /usr/bin
- RUBYGEMS PLATFORMS:
- ruby
- x86_64-linux
- GEM PATHS:
- /usr/lib/ruby/gems/1.8
- /home/adam/.gem/ruby/1.8
- GEM CONFIGURATION:
- :update_sources => true
- :verbose => true
- :benchmark => false
- :backtrace => false
- :bulk_threshold => 1000
- REMOTE SOURCES:
- http://rubygems.org/
Im not hot with paths etc but all the gem directories listed above are on the path so how come it cant find the command?

Answer 1

Your $PATH variable needs to include the exact path to your Ruby's bin directory. Adding a directory to the PATH does not include it's subfolders. Try adding the bin directory via:
export PATH=$PATH:/home/adam/.gem/ruby/1.8/bin
or if you installed the gem using sudo:
export PATH=$PATH:/usr/lib/ruby/gems/1.8/bin
You might want to add this to your .bashrc file, so that you don't have to set this manually every time your open up a new bash.

Answer 2

(Just stealing #John Franklin's comment)
$ gem environment
Will tell you the EXECUTABLE DIRECTORY. Then put whatever that value is in your PATH like so (in your .bashrc or other shell config file).
export PATH="$PATH:/path/to/bin"
Reload your shell and you should then be able to use the installed gem.

Answer 3

If you use RVM (most do), then it will take care of this for you. In fact putting it in your path directly may conflict. You have to set a ruby to use though. Run one of these on the command line.
rvm use 1.9.3
or
rvm use --default 1.9.3