samba 2.x used to log like this: ps-gurari (9.148.8.114) connect to service c$ as user nobody (uid=65534, gid=65533) (pid 1766) samba3 doesn't log the netbios names: 9.143.168.226 (9.143.168.226) closed connection to service c$ the netbios name does not appear anywhere.
%m seems also to have problems when used in preexec ...
without full log files, my guess is that these are Windows 2k or above clients connecting to port 445 (smbd in Samba 3.0 supports port 139(netbios) and port 445(no netbios)) so there is no name to be logged. Is this your case? You can set "smb ports = 139" in smb.conf to force netbios only connections.
yes, sorry, you are right I think. Maybe it would be a good idea to mention this in the howto for migrations from samba2 to samba3.
no bug
originally reported against 3.0.0beta1. CLeaning out non-production release versions.