Stopping access to machines that don't have an in-addr.arpa. entry

Hi,

Is there an easy way to stop squid from fetching pages from machines that
don't have a valid in-addr.arpa entry?

It seems that a lot of the porn sites just use IP addresses now, and I'd
like to stop access to those sites.

I can do it in my redirector, but if someone knows of a better way, could
they please let me know.

Thanks
Gavin

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| Gavin Cameron                       |             Ormond College           |
| Ph    : +61 3 9344 1201             |      The University of Melbourne     |
| Fax   : +61 3 9344 1111             |          Parkville,  Victoria        |
| Email : gavin@ormond.unimelb.edu.au |            Australia,  3052          |
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