Why can't I write this file?

[Julien Gabel]

> I just changed the permission and ownership of some files and was
> denied writting to this file even though I'm in the group and the
> group has write permissions. Did I forgot something or is this
> strange? I thougth I should be able to write as user akruijff
>
> ls -loa
> drwxrwxr-x   2 www       www       -  512 Mar  8 21:57 ./
> drwxr-xr-x  16 akruijff  akruijff  - 1024 Mar  6 18:48 ../
> -rwxrwxr-x   1 www       www       - 4743 Mar  8 21:52 file.php*
> -rwxrwxr-x   1 www       www       - 2431 Mar  8 21:53 functions.php*
> -rwxrwxr-x   1 www       www       -  299 Mar  7 00:20 preview.php*
>
> cat /etc/group
> www:*:80:akruijff
>
> cat /etc/passwd
> akruijff:*:1001:0:Alex de Kruijff:/home/akruijff:/bin/csh

What says the id(1) command on the same term?

-- 
-jpeg.