title: Git - fatal: Branch name doesn't conform to GIT standards
body: <p>I am trying to migrate a CVS repo to Git using cvs2git.
  Unfortunately my cvs repo has many branches with regex.
  While doing git fast import(unix) it reports the error below</p>
  
  <pre><code>fatal: Branch name doesn't conform to GIT standards: refs/tags/Release21_3_4_0_0_3_7_10[3_8_4_3]
  fast-import: dumping crash report to .git/fast_import_crash_27083
  </code></pre>
  
  <p>I tried to delete these tags, but no luck. i think it is taking the entire history.
  I am not able to import the HEAD alone also.</p>
  
  <p>How do i resolve this?</p>