[quote user="Nikolas"]Is it true that POP3 and IMAP user names and passwords cannot be sent encrypted?[/quote]

Not really, the connection you use to the server can be an SSL/TLS encrypted tunnel so that all traffic, including the user/pass authentication, won't be accessible.  Most modern clients support SSL connections.

I have setup my MERCURY SMTP server for POP3 access.

I have done some research on POP3 and read that user names and passwords are sent in plain text format, so this level of security is not satisfactory enough to will allow me to sleep at night.

I have done some research on IMAP and have read user names and password are also sent in plain text.

Is it true that POP3 and IMAP user names and passwords cannot be sent encrypted?