[squid-users] Special error message possible?

I want to block access to internal websites via the proxy. I want to
do this on the proxy itself, but I'd like to show the user a proper
error message like:

"Don't access the internal net by means of the proxy".

Is that possible?

-- 
Ralf Hildebrandt (i.A. des IT-Zentrums)         Ralf.Hildebrandt@charite.de
Charite - Universitätsmedizin Berlin            Tel.  +49 (0)30-450 570-155
Gemeinsame Einrichtung von FU- und HU-Berlin    Fax.  +49 (0)30-450 570-962
IT-Zentrum Standort CBF                 send no mail to spamtrap@charite.de