sshd not logging Invalid user



On Fedora core, with

kernel 2.6.14-1.1653_FC4
and
openssh-4.2p1-fc4.1

sshd was logging Invalid user in /var/log/secure
up to a few days ago, but now it is not. The sshd
log level is set to VERBOSE. It could be something
I did, but what?

Thanks for your help.
Mike.
.