I can\'t login to github with generated ssh-keys. I\'ve followed this manual: http://help.github.com/linux-key-setup but at step:
ssh git@github.com <
ssh git@github.com
After generating the ssh keys I executed the command listed below as suggested by jamesw.
$ ssh-add ~/.ssh/id_rsa
I entered my password. Then retried to clone the heroku repository. This time it worked fine.