802.1x md5

[fabianochoueiri@yahoo.com.br]

Hi, I am trying to use 802.1x md5 authentication in a T38g phone. I have configured user name and password. When there is no PC conected to the phone, the authentication do not work. It does not event happen. When I Connecticut a PC on the phone (configured with 802.1x authentication too), the authentication works. Both PC and phone are authentication but few minutes later the phone is deauthenticated. What AM I missing ?