Import issues, keeping IDs / forcing IDs


I’d like to migrate an opensource project to github (from redmine).
With the importer and the API I’ve done almost everything I wanted (code, wiki…), but I’d like to import issues with their legacy ID.

Is there any way to import issues keeping IDs (create issue and force the ID) ? It’s important for us as the issue IDs are mentioned in other wikis/documents/sites…

Thanks a lot