[squid-users] how to remove unknown headers?

I have these two statements in my squid cache config:

anonymize_headers deny via
anonymize_headers deny x_forwarded_for

The first one seems to be working fine. The second one is ignored.
I get this message on startup:

parse_http_header: Ignoring unknown header 'x_forwarded_for'

I also have this configuration:

forwarded_for off

but that's not what I want. It change the IP address to "unknown".
What I want to do is make the existance of cache 100% transparent
and that includes totally removing any added headers. Is there a
way to do this without hacking the source?

-- 
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| Phil Howard - KA9WGN |   Dallas   | http://linuxhomepage.com/ |
| phil-nospam@ipal.net | Texas, USA | http://phil.ipal.org/     |
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