Today I went to login in the admin console https://zimbra.server.net:7071/zimbraAdmin/ with the admin and password credentials. I got an "Authentication Falied" error message.
I am running Zimbra 6.0.4 Open Source Edition on Centos5.4.
Next, I started an SSH session and logged in as zimbra:
zmprov sp firstname.lastname@example.org pwd
Went back to https://zimbra.server.net:7071/zimbraAdmin/ and tried logging in as admin/pwd. Same error message. Next I tried with email@example.com/pwd. Again, same error message.