Strange Update-Bug in postgres (is it a feature?) ?!

Hi!

Is this a bug or a feature:

When I try an update like this
"update mail set mail.mailread=1 where mail.mail_id=123" I get the Error
"Error while executing query parse error near '.'"

Then I try

"update mail set mailread=1 where mail.mail_id=123" and it works fine ...

On MS-SQL both work fine ... since I use finals for the tablefields in my
java-program to build the queries/updates from, it's kinda bad if I remove
the table in front of the field (because they could be used in updates as
well as joined-selects where i would need them!) ... So it would be great if
both versions would work as they do on other DB-Systems ... why is that
different ... does that serve a certain purpose ?!

Any chance to change that behaviour ?!

Regards ... Manuel ...