bash: capify: command not found

I'm trying to deploy my rails app from my local machine to my server.
I'm using Ubuntu.
I've run:
sudo gem install --include-dependencies rake
sudo gem install --include-dependencies rails
sudo gem install --include-dependencies termios
sudo gem install --include-dependencies capistrano
sudo gem install --include-dependencies mongrel
sudo gem install --include-dependencies mongrel-cluster

But when I try (in the rails project root):
capify .

I get:
bash: capify: command not found

F1 for Help?

Thanks.