Rolf (&Sibylle),

> function NOW is defined in the database as
> DECLARE EXTERNAL FUNCTION NOW
> RETURNS TIMESTAMP
> ENTRY_POINT 'getExactTimestamp' MODULE_NAME 'fbudf.dll';

even if this doesn't help you with the UDF, but why do you want to use
an udf function for something that's available anyway?

SELECT CAST ('NOW' AS DATE) AS SERVER_DATE
FROM RDB$DATABASE

or

SELECT CAST (CURRENT_TIMESTAMP AS TIMESTAMP)
AS SERVER_DATE FROM RDB$DATABASE

or with dialect 3:
(CURRENT_DATE, CURRENT_TIME, ...)
...

will also work.

Luc.