[Dovecot] Setting up a local shared mailbox

One: I have never set up an IMAP server before, so I thought I would ask 

first before blindly stumbling around. The problem I am want to solve is this: my wife and I have a "joint" email account that we both want to access (we also have our own personal accounts, but that's beside the point.) I posed the question to my local LUG, and several suggested setting up a local IMAP server so that we can both access it through KMail. Would you concur? If so, is there a tutorial or something similar that gives instructions for setting up dovecot locally? As I said, I've never set up an IMAP server before, and I'm not really sure how to go about it. (I'm running Debian Sid, so the packages are already installed, but I don't know what additional steps need to be taken.) Thanks for your help, :Peter