> I've heard that this is a new feature of FB 2.0 but I can't find an
> example SQL statement.

The difference is that in older FB versions, only SYSDBA was allowed
to modify security database, while in FB2 even ordinary users
can modify their passwords (but not passwords of other users, of course).
However, the methods are still the same, i.e. gsec or services api
(in older versions it was also possible to modify security database directly,
which is now forbidden in FB2)

Ivan