The SquirrelMail website has a quick tutorial about IMAP feature extensions like server side SORT and what not.
Here: http://www.squirrelmail.org/wiki/SquirrelMailPerformance
Quote:
> telnet imapserver.example.com imap
* OK
2 capability
* CAPABILITY IMAP4rev1 UIDPLUS CHILDREN NAMESPACE THREAD=ORDEREDSUBJECT THREAD=REFERENCES SORT QUOTA IDLE AUTH=PLAIN STARTTLS
2 OK CAPABILITY completed
You want to look for "SORT" and "THREAD" as the most important features.
STARTTLS upgrades a plaintext connection to encrypted (SSL or TLS, but really TLS these days), this saves a port, and I guess documentation - everything just could use the old port 143. Confusion ensues because this was slapped on AFTER encrypted-only IMAP ports (993) became well used.
https://www.fastmail.com/help/technical/ssltlsstarttls.html
More confusion. Typically once you're set up for encrypted IMAP, encrypting the password is redundant. So, usually this is plaintext. This is the configuration Google uses.
tags: IMAP