Microsoft recently released a new version of Windows Azure Active Directory Sync, better known as DirSync. As the information on the Version Release History page of the tool depicts, this new build allows you to deploy DirSync on a Domain Controller.
Along with this new ability, this new version (6553.0002) also includes some fixes:
- Fix to address Sync Engine memory leak
- Fix to address "staging-error" during full import from Azure Active Directory
- Fix to handle Read-Only Domain Controllers in Password Sync
The latest version can be downloaded from the following page: