[squid-users] [Squid] Invalid Response

I have a problem when visit some site(only with ie7 and ie8)
i use redhat 5 squid 2.6stable21

return me this error

ERROR
The requested URL could not be retrieved

While trying to process the request:
GET /esystem/asp/login.asp HTTP/1.0
Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg,
application/x-shockwave-flash, application/vnd.ms-powerpoint,
application/vnd.ms-excel, application/msword, application/xaml+xml,
application/vnd.ms-xpsdocument, application/x-ms-xbap,
application/x-ms-application, */*
Referer: http://www.abilearning.it/esystem/index.asp
Accept-Language: it
Proxy-Connection: Keep-Alive
Host: www.abilearning.it

The following error was encountered:
Invalid Response
The HTTP Response message received from the contacted server could not
be understood or was otherwise malformed. Please contact the site
operator. Your cache administrator may be able to provide you with
more details about the exact nature of the problem if needed.

i try to use this:
acl broken dstdomain abilearning.it
header_access Accept-Encoding deny broken

but not work in the cache.log there isn't any error and i try to use
relaxed_header_parser warn

Thanks Jacopo

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Linux, Windows Xp ed MS-DOS
(anche conosciuti come il Bello, il Brutto ed il Cattivo).
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