> I> ISO8859_1.PT_BR
> I> WIN1252.WIN_PTBR
>
> they sure are. :-)
> But I don't think they are AI, are they?

Look at column RDB$COLLATIONS.RDB$COLLATION_ATTRIBUTES, it contains flags
PAD-SPACE (1)
CASE-INSENSITIVE (2)
ACCENT-INSENSITIVE (4)

And then try this to find "special" collations:

SELECT RDB$COLLATION_ATTRIBUTES, RDB$COLLATION_NAME
FROM RDB$COLLATIONS
WHERE RDB$COLLATION_ATTRIBUTES > 1;
================
7 PT_BR
7 WIN_PTBR
3 WIN_CZ
7 WIN_CZ_CI_AI

Ivan