Caching MS-compressed files

Hello all.
        I have a small problem with the way that squid caches files. I have a
file called readme.tx_ which is a ms-compressed file. When squid
downloads this file it downloads it as a text file (ascii file). Now
this causes the file to be corrupted once downloaded from the proxy
server. I added an entry for this particular but this will happen for
any ms-compressed files where they substitute the last letter of the
extension for the '_' character. Does anyone know how to fix the above
problem. Any help would be greatly appreciated.

-- 
Regards,
    Kurt Heine
    Information Services Support Officer
    Burnie City Council
    phone : 03-6430-5737
    fax     : 03-6431-3896
    email : kheine@burnie.net
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