qmail-pop3d logs

[DOODS]

Hi to everyone!
I have separate log files for qmail, smtpd and qmail-pop3d. But I notice that my pop3d 
logs doesn't show the 'username' or any 'incorrect password' messages. How can I get my
qmail-pop3d to log usernames that access their mails? I need this to make sure that a
certain client gets his mails. BTW, I'm using tcpserver with my qmail-pop3d.

Thanks for any help and more power!