On our JIRA system the Bitbucket Importer Plugin for JIM is istalled, but the version 1.0.3. I am a bit suprised, how it comes, because acc. to the version history on the Atlassian Marketplace, version 1.0.3 was released for JIRA Server 6.0-beta1 - 6.0.8.
If it has been pre-installed with Jira, so we should have at least version 1.0.4 for JIRA Server 6.0.1 - 6.2.7. I am not sure, if it is important to have it updated, since we use the JIRA importers Plugin (JIM).