IMAP, YouMAP, WeMAP: Mail Protocol's Proponents Argue for Better Support
wired.com
wired.com
Although after you get far enough into the syntax you start to see why the protocol is as complicated as it is. The protocol itself is written as a series of design patterns so each command had a predictable request pattern and a response pattern. After you get past the initial parsing of the command and response strings the protocol become much easier IF you think of them as a series of patterns.