It should be possible to whitelist licenses. Whitelisting licenses is safer than maintaining a list of incompatible licenses as you can't accidentally include a recipe with a license that hasn't been reviewed and accepted.
I realize this is an old bug, but are you requesting functionality that is not satisfied by the LICENSE_FLAGS_WHITELIST variable?
(In reply to comment #1) > I realize this is an old bug, but are you requesting functionality that is > not satisfied by the LICENSE_FLAGS_WHITELIST variable? That is a whitelist for LICENSE_FLAGS. This request is a whitelist for LICENSE which is different.