New RC, Login not possible, only cram-md5?!

[2ee]

Dear folks,

just upgraded from 0.2 to 0.2.1, config was verified etc.
The problem is, that now logins are not possible anymore. Looking into the mail.log it contains "imapd: LOGIN FAILED, method=CRAM-MD5, ip=[::ffff:127.0.0.1]" I am wondering why RC chooses cram-md5 if i configured it to use plain.
Unfortunately RC itself does not write anything into the logfiles, although the path is correct, loglevel is set to 8 (trace) and log dir is writeable.

It worked in the same constellation before, without any problems.
Any ideas?