Squid + Special group enable NAT Access

Hi all,

I'm wondering if it is possible to make squid call an external script or 
binary (even better natively) to enable NAT access to specific user group.

The scenario is: I have a network where everyone should have 
restrictions, use the proxy to surf the Internet as is an usual squid 
implementation. BUT, I need to allow full NAT access to stations, based 
on username, such an user would be the network admin.

EG: if a common worker logs in, no extra NAT access will be allowed, 
proxy only access, blocking MSN an everything else necessary. I am an 
admin, inside the group "full_access"  and I need full NAT access to the 
world, but i need this while I'm logged to a station, no matter what 
station I'm logged on. Logging off will remote my NAT rights for the IP.

Did I make myself clear?
Is it possible? Any hints?

Thanks!

Mauricio

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fn:Mauricio Silveira
n:Silveira;Mauricio
org;quoted-printable:FSN do Brasil - Consultoria em Inform=C3=A1tica;Software Development / Networking
adr:;;;;;;Brazil
email;internet:[email protected]
title:Linux Consultant / Developer
tel;cell:11-9949-1040
url:http://www.fsndobrasil.com
version:2.1
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