> Is that mean, I can use FB2 to connected with DB with ODS 10.1 without
> problems? In other word, the FB2 can replace and act like 1.5 on ODS
> 10.1 (so I just run FB2 to handle ODS 10.1 and ODS 11. And just
> shutdown FB 1.5).

Two considerations:

1. Firebird 2 rejects some queries 1.5 accepts, especially if you
declare aliases for tables then use the table name elsewhere in the query.

2. A lot of the improvements in Firebird 2 (garbage collection, index
size restrictions, etc) are unavailable until you change the ODS.

So if you have already installed FB 2 and your queries have already
been confirmed to work under FB 2, then you might as well switch them
completely over.

Adam