access challenge on empty password

Hi, I use pam_radius with openssh on a FreeBSD box. When I authenticate, and for the first time I simply enter an empty password then the second time I am prompted for the password characters are echoed on the terminal. As I can see my freeradius server responses an access challenge to request with an existing user and empty password combo. Is this a normal behaviour? How can I configure the system not to do so? Thanks! -- View this message in context: http://freeradius.1045715.n5.nabble.com/access-challenge-on-empty-password-t... Sent from the FreeRadius - User mailing list archive at Nabble.com.