[squid-users] squid internet limits

hi
using squid version 2.5STABLE9, debian sarge testing.
i want to limit my internet users if they are in specific groups to have a
certain number of hours per day
so if a user logs on at 8 in the morning they may have if they log on to
the staff group 4 hours, if they are a part of the volunteer group they
may be limited to 1 hour of total internet per day so even if they use the
net for 30 minutes from 9 until 9:30 and then log off come back and log on
again at 11, they will only have 30 minutes left of internet usage.
i saw the post about authpf but i can not find a debian package nor
anything on the system to suggest that the shell is available.
are there other packages i could use or a way to do this using acls or
some such?
thanks
Jack

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