[squid-users] Authentication logging

Hello,

Using squid 2.7 stable 9, I have set the debug_options to 29,2 which
logs authenticated users, e.g:

   user 'xxx' has been seen at a new IP address (11.22.33.44)

However, is there a way I can log unsuccessful authentication attempts?
I have increased the debug level to 6, but it still doesn't log
authentication failures. Is this possible in the squid 3.x series?

Thanks,

John.

-- 
John Horne, University of Plymouth, UK
Tel: +44 (0)1752 587287    Fax: +44 (0)1752 587001