Our trac admins report that this is caused by users who don't have their
email authenticated (that is, Trac sends you a test email, and you
confirm that you got it, so Trac knows the address is valid). When we
upgraded, existing users needed to re-authenticate their email
addresses, but the upgrade process doesn't include resending the
authentication emails.
When you update your email address in trac, it should resend the
authentication request. Once you confirm the change, you'll be set.
Allison