I think it's possible. Have you tried it and failed?
No, it's not possible in Outlook 2003.
Judy Gleeson has provided the following workaround to overcome the new way
Outlook 2003 sorts the "By Category" view:
Use the Detailed or Simple List view, show the columns you want to see
(field chooser), click the column (eg Last Name) you want to sort by, THEN
use the group by box to group by Category. That should have alphabetical as
well as the grouping.

Signature
Russ Valentine
[MVP-Outlook]
>I think it's possible. Have you tried it and failed?
>
>> I'd like to be able to group by category, then sort by clicking a column
>> heading, without losing The grouping. Is that Possible in outlook 2003?