title: git push: refs/heads/my/subbranch exists, cannot create
body: <p>Is this not possible to create somme sub-sub-folder in a repo on a server?</p>
  <p>if i do:</p>
  <pre><code>git push origin dev/master 
  </code></pre>
  <p>everything work find</p>
  <p>but if i do</p>
  <pre><code>git push origin dev/sub/master
  </code></pre>
  <p>i got this:</p>
  <pre><code>error: 'refs/heads/dev/sub' exists; cannot create 'refs/heads/dev/sub/master'
  </code></pre>
  <p>i checked with <code>git branch -r</code> and directly with ssh, there isn't dev/sub folder already created.</p>
  <p>what's wrong?</p>