Heroku - How can I undo a push on heroku?

After pushing my app on heroku, my app crashes. I don't want to make a git rebase before getting heroku last version (if I do so, I'll get fast-forward errors...)

I would be plea开发者_如何学编程sed to know if there is a command to do it (I don't find it on the heroku doc)

Thank you!

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actually now heroku has a rollback!

http://blog.heroku.com/archives/2010/11/17/releases/

heroku rollback

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Use git push heroku --force to push your local HEAD.