[Orgmode] Relative dates with sexep

[julien cubizolles]

I'm trying to specify a date relative to another date in an org file.
I've tried to adapt one of the examples from worg, with :

 <%%(= 7 (- (calendar-absolute-from-gregorian date)
            (calendar-absolute-from-gregorian (02 02 2010))))>

to get the date one week after the 2nd of february 2010. Bad sexp...

What should I use ?

Julien.