wtf heroku 1.20.0 is disappeared

1.20.0 April 4, 2011 yanked
man, please never do this!
this is not funny!

-----> Gemfile detected, running Bundler version 1.0.7
       Unresolved dependencies detected; Installing...
       Fetching source index for http://rubygems.org/
       Could not find heroku-1.20.0 in any of the sources
       FAILED: http://devcenter.heroku.com/articles/bundler
 !     Heroku push rejected, failed to install gems via Bundler