[otrs] Panic! No UserData for use

Howdy ;) A New Customer of ours has been unable to login to OTRS for the first time :( Mon Oct 27 17:29:13 2014 notice OTRS-CGI-10 Panic! No UserData for user: 'xyz'!!! Mon Oct 27 17:29:13 2014 error OTRS-CGI-10 No UserID found for 'xyz'! Mon Oct 27 17:29:13 2014 error OTRS-CGI-10 No UserID found for 'xyz'! Mon Oct 27 17:29:13 2014 notice OTRS-CGI-10 User: xyz authentication ok (REMOTE_ADDR: SNIPPED). Both the user's Customer acct and CustomerID group exist. We are NOT using LDAP, only RADIUS for authentication. We are using OTRS 3.3.9 on CentOS release 6.5 The user data is stored in the OTRS DB itself. *Thanks in advance for any clues/ideas/suggestions! *