this query generates weeknumbers, and shows what the system think is
the latest week:
SELECT * , WEEK( datetime )
FROM tigerens_kodetslyst .kodets_lyst_salg
WHERE id >0
ORDER BY `id` DESC

The week column is 38 for posts from today

But my danish mobile phone says its week 39, and thats what this
authorative webpage also says: http://timeanddate.com/calendar/?year=2007&country=2

the 27th of september 2007 is week 39.

Whats wrong?