Syntax Check: Group BY with Joins

[Eric Ellsworth]

Hi,
    I'm having trouble with this query:

SELECT Max(DATE_ADD('1970-1-1',INTERVAL Lastupdate/3600/24 DAY)) as BaskDate, 
ofm_baskets.Code, Sum(ofm_baskets.Quantity) AS TotalQty
FROM (ofm_basklist INNER JOIN ofm_basklupd ON ofm_basklist.Session_id = 
ofm_basklupd.Session_id) INNER JOIN ofm_baskets ON ofm_basklist.Basket_id = 
ofm_baskets.Id
GROUP BY ofm_baskets.Code
HAVING (((ofm_basklist.Order_id)=0))
ORDER BY Max(DATE_ADD('1970-1-1',INTERVAL Lastupdate/3600/24 DAY));

I get the following error:
ERROR 1111: Invalid use of group function

Can someone give me an idea of what's wrong with this query?  I'm using MySQLd version 
4.0.16.

Thanks,

Eric