relayhost mail.arcor.de needs encryption

[Henning]

Hi,

reconfiguring my kolab 3.1 postfix I noticed that my used relay 
mail.arcor.de really needs smtp encryption (you should use it anyway), 
so you have to set main.cf

# Postfix Relay Host
relayhost = [mail.arcor.de]:25
# force encryption of outgoing mail ("may" would also work)
smtp_tls_security_level = encrypt

or you would experience "Server configurations problems (in reply to 
RCPT)" and no successfully outbound mail.

regards,
Henning