When you assume a role in a project your codehaus email account is typically automatically added to some mailing lists (ie: dev or scm). Hence, check the file ~/.forward and put the email address you want all emailed sent to yourusername@codehaus.org to be forward to.

If you want to post on one of these mailing lists you either configure your client to send emails as yourusername@codehaus.org or the first time you try to post ask one of the despots to allow your email account: any subsequent post from that account will be accepted by the mailing list server.