>I'm sure the calling convention for UDFs is cdecl !!!! stdcall is probably
>what is messing things up.

o.k. I changed it, but the result is still the same.

If this would be the reason for the problem, why does the statement

select test_udf (1, 2, 2.9) from rdb$database

work as expected and

select test_udf (:a, :b, :c) from rdb$database

doesn't?

cu
Helmut