I got this error :
"An error occured while logging in with account: User name: agnez_mipsum, Server name: nonoh.net. This is most probably an internal application error. Please report the problem to our developers mailing list (email@example.com)."
After making a call via nonoh.net
I was able to make one call, then got the error message. After that no further calls wer possible, even after restartng sip-communicator (1.0-alpha3-nightly.build.2414).