The InterBase 6 core team made a decision for IB6 _not_ to support ODS 9
(i.e. 5.x databases) in order to simplify the scope of the IB6 QA
effort.

The QA team was buried with requirements to write tests for new
features, in multiple SQL dialects, and to support more platforms (in
all permutations of client and server). Adding another dimension of ODS
version to their test suite was not something that team could
accomodate, with the given schedule.

So, though InterBase architecture supports the _capability_ for the
engine to understand the ODS of a previous versions, IB6 deliberately
does not support it.

If it's feasible to do so, I think it'd be great for IB 6.x (where x >
0) to add this capability. However, I would prefer to see 6.0 be
released _without_ this capability, just so folks can use it. If we
demand more features from IB 6.0, it'll just delay its release. I don't
think it's too complex or unreasonable to require a gbak&restore to
migrate one's databases to IB6 (dialect 1).

Bill Karwin