>>What if a not too small customer asks about Oracle, DB2, PostgreSQL or even dbf again <g>?
Invest 15% more of your time now to work through exchangable layers.

I've been doing this a long time and I"ve NEVER seen a client replace one client-server backend with another and retain the original front and middle tiers.
I've done scads of conversions from .dbf to SQL Server, etc, but not one single switch between client-server backends.
Are things different in the large company market?

That said, since we use SPT with vanilla ANSI SQL and try to stay away from proprietary features where possible, I'm wondering how big a deal it would be to switch to go_sql, for example?
I've seen examples of SPT code accessing go_sql tables and the code was almost identical to the code we use to access SQL Server tables.