I'm working off these instructions: http://github.com/dcparker/ruby-gmail

From the home directory I do a standard install and good stuff happens:

Johnny-Goodmans-MacBook-Pro:gmail johnnygoodman$ sudo gem install ruby-gmail

Successfully installed ruby-gmail-0.2.1
1 gem installed
Installing ri documentation for ruby-gmail-0.2.1...
Installing RDoc documentation for ruby-gmail-0.2.1...

I head over to my ~/www dir where I run scripts that include other rubygems successfully and create a gmail directory. I create a script that includes rubygems and gmail, but does nothing else:

Johnny-Goodmans-MacBook-Pro:gmail johnnygoodman$ pwd
/Users/johnnygoodman/www/gmail
Johnny-Goodmans-MacBook-Pro:gmail johnnygoodman$ ls
test-send.rb
Johnny-Goodmans-MacBook-Pro:gmail johnnygoodman$ cat test-send.rb 
require 'rubygems'
require 'gmail'

I run this script and the errors begin:

Johnny-Goodmans-MacBook-Pro:gmail johnnygoodman$ ruby test-send.rb 
/Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `gem_original_require': no such file to load -- mime/message (LoadError)
        from /Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `require'
        from /Library/Ruby/Gems/1.8/gems/ruby-gmail-0.2.1/lib/gmail/message.rb:1
        from /Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
        from /Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `require'
        from /Library/Ruby/Gems/1.8/gems/ruby-gmail-0.2.1/lib/gmail.rb:168
        from /Library/Ruby/Site/1.8/rubygems/custom_require.rb:36:in `gem_original_require'
        from /Library/Ruby/Site/1.8/rubygems/custom_require.rb:36:in `require'
        from test-send.rb:2
Johnny-Goodmans-MacBook-Pro:gmail johnnygoodman$ 

Here's my gem env:

Johnny-Goodmans-MacBook-Pro:gmail johnnygoodman$ gem environment
RubyGems Environment:
  - RUBYGEMS VERSION: 1.3.7
  - RUBY VERSION: 1.8.7 (2009-06-08 patchlevel 173) [universal-darwin10.0]
  - INSTALLATION DIRECTORY: /Library/Ruby/Gems/1.8
  - RUBY EXECUTABLE: /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby
  - EXECUTABLE DIRECTORY: /usr/bin
  - RUBYGEMS PLATFORMS:
    - ruby
    - universal-darwin-10
  - GEM PATHS:
     - /Library/Ruby/Gems/1.8
     - /Users/johnnygoodman/.gem/ruby/1.8
     - /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8
  - GEM CONFIGURATION:
     - :update_sources => true
     - :verbose => true
     - :benchmark => false
     - :backtrace => false
     - :bulk_threshold => 1000
     - :sources => ["http://rubygems.org/", "http://gems.github.com"]
  - REMOTE SOURCES:
     - http://rubygems.org/
     - http://gems.github.com 

The path that the errors give when I run the script is not the same as the GEM PATHS given in the env output. However, I don't know how to make them match or if that's the significant thing here.