[Users] Can't login with the user 'admin'

[Mark Wu]

After upgrading ovirt-engine (new version: 
ovirt-engine-3.1.0-3.1345126685.git7649eed.fc17),  I can't login with 
the user 'admin'.   Here's my upgrade process:
yum remove ovirt-engine
yum install ovirt-engine
engine-setup   and type the same password for 'admin' as before.

The setup script finished successfully. But I can't login with 'admin' 
user.   I tried to run engine-setup again, but it didn't help.

I also tried to change password with engine-config:

# engine-config -g AdminPassword
Failed to decrypt the current value
# engine-config -s AdminPassword=xxxxxxxx
'xxxxxxxx' is not a valid value for type Password.

It always complains it's not a valid value whatever I input.

Is there anyone hit problem before?  And any idea about how to resolve it?
Thanks