help with date_part & day of week

hi list

from the user manual:
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dow
The day of the week (0 - 6; Sunday is 0) (for timestamp values only)
SELECT EXTRACT(DOW FROM TIMESTAMP '2001-02-16 20:38:40');
Result: 5
Note that extract's day of the week numbering is different from that of
the to_char function.
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now it happens that in europe it is common to have monday as the first day
of week. as far as i know, mssql uses the local os setting for determining
which value should be returned for a sunday. one select statement we're
trying to migrate from mssql to pgsql depends on the ordering of records
according to their day of week value - where monday is the first day. how
can this be fixed in pgsql?

the (simplified) query in question:
SELECT date_part('year', date_added) AS year, date_part('week', date_added)
AS week, date_part('dow', date_added) AS day, id FROM entries ORDER BY year,
week, day

btw: date_part('week', ...) already recognizes monday being the first day of
week accordingly to ISO-8601.

thanks,
thomas