Rubygems permissions problem in Leopard.

Question

I've been struggling to get a rails development environment. I've installed ruby and rubygems through macports, and they are both running from /opt/local/bin. But apparently some permissions are hosed - I've gone through and chmodded all directories I can find related to rubygems, but I'm still unable to run rubygems without a sudo. At this point I'd love to just wipe everything and start fresh, but I'm not even sure where to begin. Any ideas?

Below is the error as well as my environment:

slip /bin: gem environment
/opt/local/lib/ruby/site_ruby/1.8/rubygems/source_index.rb:91:in `read': Permission denied - /opt/local/lib/ruby/gems/1.8/specifications/actionmailer-2.3.8.gemspec (Errno::EACCES)

My environment:

    RubyGems Environment:
  - RUBYGEMS VERSION: 1.3.7
  - RUBY VERSION: 1.8.7 (2010-01-10 patchlevel 249) [i686-darwin10]
  - INSTALLATION DIRECTORY: /opt/local/lib/ruby/gems/1.8
  - RUBY EXECUTABLE: /opt/local/bin/ruby
  - EXECUTABLE DIRECTORY: /opt/local/bin
  - RUBYGEMS PLATFORMS:
    - ruby
    - x86-darwin-10
  - GEM PATHS:
     - /opt/local/lib/ruby/gems/1.8
     - /Users/slip/.gem/ruby/1.8
  - GEM CONFIGURATION:
     - :update_sources => true
     - :verbose => true
     - :benchmark => false
     - :backtrace => false
     - :bulk_threshold => 1000
     - :sources => ["http://gems.rubyforge.org", "http://gems.github.com"]
  - REMOTE SOURCES:
     - http://gems.rubyforge.org
     - http://gems.github.com