we actually copy verified bugs from Bugzilla into an internal bug tracking system, and we then use that internal bug tracking system to drive bugs to resolution
What an utter waste of effort! For more time spent doing grunt work, you give slower and less complete feedback to your customers (platform developers in this case). There may be some information they don't want in a public tracker, but I'm betting it's:
- a lot less information than they think; and
- much easier to manage in a different way, as opposed to maintaining two bug databases!