title: Modify the Commit Message of a Pushed Commit. (Mercurial)
body: <p>I created a dummy repository on bitbucket to try to learn how to do this. I've seen this done in Git, but I am unsure if this is possible in Hg.</p>
  
  <p>I have the following hg log:</p>
  
  <pre><code>changeset:   3:742dd9f71f46
  tag:         tip
  user:        RHsu
  date:        Tue Apr 09 09:58:55 2013 -0400
  summary:     added some text to 3
  
  changeset:   2:dd431695edcd
  user:        RHsu
  date:        Tue Apr 09 09:58:30 2013 -0400
  summary:     Let's try to amend this commit
  
  changeset:   1:b59ed9c945f9
  user:        RHsu
  date:        Tue Apr 09 09:58:15 2013 -0400
  summary:     added some text to t1
  
  changeset:   0:a8a24f3831ab
  user:        RHsu
  date:        Tue Apr 09 09:52:32 2013 -0400
  summary:     Add text files for testing
  </code></pre>
  
  <p>These changesets have been pushed  to bitbucket. How can I ammend the commit message of changeset2?</p>
  
  <p>EDIT: I have tried using <code>histedit</code>, but that only changes local commits. Then when I push, two heads are created.</p>
  
  <p>EDIT: Different from the other question since this question deals with editing a commit that has been pushed onto bitbucket. </p>