rbenv で新しめの ruby をインストールしたい

gistfile1.sh

$ ruby-build
ruby-build 20121104
usage: ruby-build [-k|--keep] [-v|--verbose] definition prefix
       ruby-build --definitions
$ brew unlink ruby-build
Unlinking /usr/local/Cellar/ruby-build/20121104... 4 links removed
$ brew install --HEAD ruby-build
==> Cloning https://github.com/sstephenson/ruby-build.git
Cloning into '/Library/Caches/Homebrew/ruby-build--git'...
remote: Counting objects: 87, done.
remote: Compressing objects: 100% (65/65), done.
remote: Total 87 (delta 33), reused 41 (delta 16)
Unpacking objects: 100% (87/87), done.
==> ./install.sh
/usr/local/Cellar/ruby-build/HEAD: 58 files, 256K, built in 10 seconds
$ ruby-build
ruby-build 20121120
usage: ruby-build [-k|--keep] [-v|--verbose] definition prefix
       ruby-build --definitions
$ rbenv install
1.9.3-p327 (省略 新しいものが入っている)
$ rbenv install 1.9.3-p327
Downloading yaml-0.1.4.tar.gz...
-> http://cloud.github.com/downloads/sstephenson/ruby-build-download-mirror/36c852831d02cf90508c29852361d01b
Installing yaml-0.1.4...
Installed yaml-0.1.4 to /Users/imaz/.rbenv/versions/1.9.3-p327

Downloading ruby-1.9.3-p327.tar.gz...
-> http://cloud.github.com/downloads/sstephenson/ruby-build-download-mirror/96118e856b502b5d7b3a4398e6c6e98c
Installing ruby-1.9.3-p327...
Installed ruby-1.9.3-p327 to /Users/imaz/.rbenv/versions/1.9.3-p327