Zimbra M3-270 Admin login problem

[phoenix]

I've just done a clean install of the latest snapshot and I can't login as Admin using FF 1.0.7 or 1.5 although IE works fine, I can login to admin account for email without problem. On both versions of FF I cleared the cache first then tried the login with authentication failure, that also happens for any user account that's been designated as admin.

This is installed on CentOS 4.2 (RHEL4).