Removing older versions of installed gemsEdit

All installed gems

sudo gem cleanup

Sample output

Cleaning up installed gems...
Attempting uninstall on rspec-0.8.1
Successfully uninstalled rspec version 0.8.1
Attempting uninstall on rubygems-update-0.9.1
Successfully uninstalled rubygems-update version 0.9.1
Attempting uninstall on rcov-0.7.0.1
Successfully uninstalled rcov version 0.7.0.1
Attempting uninstall on rspec-0.7.5.1
Successfully uninstalled rspec version 0.7.5.1
Removing spec
Removing drbspec
Attempting uninstall on rails-1.2.1
Successfully uninstalled rails version 1.2.1
Attempting uninstall on actionwebservice-1.2.1
Successfully uninstalled actionwebservice version 1.2.1
Attempting uninstall on ruby-debug-0.8
Successfully uninstalled ruby-debug version 0.8
Attempting uninstall on ruby-debug-base-0.8
Successfully uninstalled ruby-debug-base version 0.8
Attempting uninstall on rails-1.2.2
Successfully uninstalled rails version 1.2.2
Attempting uninstall on actionmailer-1.3.2
Successfully uninstalled actionmailer version 1.3.2
Attempting uninstall on actionwebservice-1.2.2
Successfully uninstalled actionwebservice version 1.2.2
Attempting uninstall on actionpack-1.13.2
Successfully uninstalled actionpack version 1.13.2
Attempting uninstall on rails-1.1.4
Successfully uninstalled rails version 1.1.4
Attempting uninstall on actionmailer-1.2.3
Successfully uninstalled actionmailer version 1.2.3
Attempting uninstall on actionwebservice-1.1.4
Successfully uninstalled actionwebservice version 1.1.4
Attempting uninstall on actionpack-1.12.3
Successfully uninstalled actionpack version 1.12.3
Attempting uninstall on rake-0.7.1
Successfully uninstalled rake version 0.7.1
Attempting uninstall on dhaka-2.0.1
Successfully uninstalled dhaka version 2.0.1
Attempting uninstall on ruby-debug-0.7.5
Successfully uninstalled ruby-debug version 0.7.5
Attempting uninstall on activerecord-1.15.1
Successfully uninstalled activerecord version 1.15.1
Attempting uninstall on sqlite3-ruby-1.1.0
Successfully uninstalled sqlite3-ruby version 1.1.0
Attempting uninstall on activerecord-1.15.2
Successfully uninstalled activerecord version 1.15.2
Attempting uninstall on activesupport-1.4.1
Successfully uninstalled activesupport version 1.4.1
Attempting uninstall on activerecord-1.14.3
Successfully uninstalled activerecord version 1.14.3
Attempting uninstall on activesupport-1.3.1
Successfully uninstalled activesupport version 1.3.1
Attempting uninstall on sqlite3-ruby-1.2.0
Successfully uninstalled sqlite3-ruby version 1.2.0
Attempting uninstall on actionmailer-1.3.1
Successfully uninstalled actionmailer version 1.3.1
Attempting uninstall on actionpack-1.13.1
Successfully uninstalled actionpack version 1.13.1
Attempting uninstall on activesupport-1.4.0
Successfully uninstalled activesupport version 1.4.0
Clean Up Complete

For another example of using this technique, see "Upgrading to RSpec 1.0.4 on Mac OS X Tiger".

A specific gem

For example, to cleanup only Dhaka gems:

sudo gem cleanup dhaka

Sample output

Cleaning up installed gems...
Attempting uninstall on dhaka-2.1.0
Successfully uninstalled dhaka version 2.1.0
Clean Up Complete