I've just done a quick test of creating a new email on CWPpro version: 0.9.8.1020
There were no issues apart from emails bouncing, due to no email validations - which didn't surprise me as the email account had just been created.
[Edit]
On a different server I see the messages undelivered and..
(temporary failure. Command output: Can't open log file /var/log/dovecot.log: Permission denied)
tester@xxcloud.xxxxxservers.com
I suspect there's a different problem with this though. Same CWPpro version but this one has all the clamd/amavis/spamassassin stuff enabled.