Starting on tuesday Oct 14th Lufthansa will introduce a new system of alphanumeric callsigns for all flights within the area of Eurocontrol. This new system replaces the old one which simply generated callsigns out of the trip number (e.g. LH230 FRA-STR became DLH230). In the future LH callsigns seem to have no logical system at all - so enthusiasts listening to ATC communication won`t be able to identify a LH flight by its callsign (e.g. LH230 will be DLH9VD shortly!).
Lufthansa and ATC hope to reduce cases of "callsign confusions" where air-traffic-controllers mixed up callsigns of aircraft within their area of competence.