> You forgot to put terminator after the Create Trigger command, i.e.
> ...
> > THEN NEW.my_number = GEN_ID(my_generator, 1);
> > END !!
> > SET TERM ; !!

Well ... this is the version the -finally :-)) - worked out
SET TERM !!;
--- added by me
CREATE TRIGGER my_before_trigger FOR my_table
BEFORE INSERT
AS
BEGIN
IF (NEW.my_number IS NULL)
THEN NEW.my_number = GEN_ID(my_generator, 1); --- <<======
END !! --- <<=====
--- added by me
SET TERM ; !!

Just to understand : Is it normal or is the paricular for Mitec SQL
Editor ?

Thanks everyone for the help !!
If I correctly undestood, I will could insert multiline statament
trought a JDBC connection without having to work with set term
statements at all.
Am I right ?

Giuliano