Problems with Authentication

Hi linuxers:

I have probles with user authentication, my Cisco is 2500 configured with tacacs+, and 8 USRobotics modems
I’m using shadow password
I have installes tacacs+ in my server, the /etc/tacacs/tac_plus.cfg has the following:
key = ptoavent
default authentication = file /etc/passwd
accounting file = /var/log/tacacs.log
default authorization = permit

I get disconnected from server when client tries to check password
any suggestion?? Thanx guys

Mario Benitez
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