apt-get update problem

[Account for Debian group mail <debian@pcez.com>]

Hello,

We have 2 (of out many) machines that will not do a apt-get update 
properly (since the 4.0 upgrade a couple days ago). These 2 machine are 
old but have working just fine. The message I get on both of these 
machines are:

Get:5 http://security.debian.org etch/updates/main Sources [56.5kB] 99% [5 Sources gzip 0]
[Waiting for headers] gzip: stdin: not in gzip format

Err http://security.debian.org etch/updates/main Sources  Sub-process gzip returned an error code (1)

Failed to fetch 
http://security.debian.org/dists/etch/updates/main/source/Sources.gz Sub-process gzip returned an error code (1)


I change the IP address for security.debian.org to see if that would make 
a change - no change.

I did a lynx on this file: "lynx http://security.debian.org/dists/etch/updates/main/source/Sources.gz";
and it worked just fine and was able to un-archive it as well.

The gzip program is the same version as on the other machines that work.

Not sure which direction to go now, anyone have an idea?

Thanks,

Ken