ex) play framework 1.2.4 をインストールする場合

デフォルトでインストールされるバージョンの確認

$ brew info play

play 2.0
http://www.playframework.org/
Not installed
https://github.com/mxcl/homebrew/commits/master/Library/Formula/play.rb
/usr/local/Library/Formula% git checkout 3caf5c5 /usr/local/Library/Formula/play.rb
/usr/local/Library/Formula% git info play

利用出来るバージョンを確認

$ brew versions play

2.0      git checkout 351d751 /usr/local/Library/Formula/play.rb
1.2.4    git checkout 3caf5c5 /usr/local/Library/Formula/play.rb
1.2.3    git checkout bee9712 /usr/local/Library/Formula/play.rb
1.2.2    git checkout 3137b6a /usr/local/Library/Formula/play.rb
1.2.1    git checkout bcdf2d5 /usr/local/Library/Formula/play.rb
1.2      git checkout 744b044 /usr/local/Library/Formula/play.rb
1.1.1    git checkout 0476235 /usr/local/Library/Formula/play.rb
1.1      git checkout eea40ff /usr/local/Library/Formula/play.rb
1.0.3.1  git checkout aa76115 /usr/local/Library/Formula/play.rb
1.0.3    git checkout 19edb1f /usr/local/Library/Formula/play.rb

1.2.4をインストールするように設定

$ cd /usr/local/Library/Formula
$ git checkout 3caf5c5 /usr/local/Library/Formula/play.rb
$ brew info play

play 1.2.4
http://www.playframework.org/
Not installed
https://github.com/mxcl/homebrew/commits/master/Library/Formula/play.rb

インストール

brew install play