Read-only column

Given a table like the following:

CREATE TABLE mytable (
    progr integer PRIMARY KEY,
    record_creation_date date DEFAULT current_date,
    ...
    other columns
    ...
);

is there a way to deny any modifications to 'record_creation_date'
without using a view?

Thanks,
Claudio

--
Claudio Succa
PERTEL - Torino - Italy
+39-011-437.4141
http://www.pertel.it
http://www.uniassist.it