SELECT count(id) AS multi_count, radius_values.name AS rname, 
usertime.name AS username,
sum(usertime.time_on) AS time_on

FROM usertime userinfo, radius_values 
LEFT JOIN usertime ON usertime.name = userinfo.name
WHERE 
radius_values.nr=userinfo.port_type AND 
radius_values.attr_nr=61 AND 
multi_id != '' AND
start_time >= 19981001000000 AND
start_time < 19981031235959  
GROUP BY multi_id   
HAVING multi_count > 1 ORDER BY userinfo.name