You have 'security = domain', the PDC says username and password is
ok, and you dont have the local unix account.
Then 2.2 will answer the session setup with login as guest, while 3.0 will
reject with LOGON_FAILURE.
This means for those accounts (Existing on PDC but not locally), access to
guest shares is not possible anymore.
I've added this as a change in behavior in the release notes.
I'm going to close it since i think mapping an authenticated
user to guest on a failure is a bug. We can re-open this
if we get a lot of flack.
originally reported against 3.0alpha23. Bugzilla spring cleaning.