Date/time formula problem

Hi,

I have problems with formulas and Date/time fields :

the following two formulas don’t match the same documents, and i don’t find out the problem :

(dateAD is a time/date field)

formula 1 : (dateAD-@date(2004;1;27))>=0 & (@date(2004;1;28)-dateAD)>=0

==> results contain documents with a dateAD=“29/01/2004 00:00:00 CET” !?

formula 2 : @day(dateAD)>=27 & @day(dateAD)<=28 & @month(dateAD)=1 & @year(dateAD)=2004

==> results are correct

any idea ?

thanks in advance