Ruby-on-rails – cap command not found

I'm using Mac OS X 10.8.2 and I installed ruby & rails with rbenv.

I try to install capistrano with

gem install capistrano

Successfully installed capistrano-2.13.5

1 gem installed

Installing ri documentation for capistrano-2.13.5…

Installing RDoc documentation for capistrano-2.13.5…

Everytime I try to install with code, It says "1 gem installed".

But, If I write

capify .

I'm getting error like this.

zsh: command not found: capify

My $PATH

/Users/lutfidemirci/.rbenv/bin:/Users/lutfidemirci/.rbenv/shims:/Users/lutfidemirci/.rbenv/shims:/Applications/Postgres.app/Contents/MacOS/bin:/Users/lutfidemirci/.rbenv/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/var/lib/gems/1.8/bin