Let me guess, they are using apache 2.0.55 as proxy...
mod_proxy in 2.0.55 has problems with properly delivering chunked
encoding.
The CGI.pm error sounds very familiar to the one I had with apache 2.0.55
proxy.

2.0.54 and 2.2.2 dont have the chunked encoding prob.

Enno

On Thu, 18 May 2006, Thomas Hilbig wrote:

> I recently updated my Linux/Apache/MP2 environment, in
> part hoping to resolve a problem that occurs with
> about 10% of my clients. These clients experience a
> timeout from my server when they submit a form using
> POST having more than about 15KB of data (from httpd
> access_log -- the actual posted data may be much less
> than this). I think it is related to their
> proxy/firewall as the same computers/users do not have
> the problem when they connect directly to the Internet
> (i.e. dial up) to access the same form pages.
>
> I can replicate the problem using a very basic CGI
> form. It uses CGI.pm and is hanging on the line "my
> $q = new CGI;" when the POSTed data exceeds the 15KB
> threshold from these clients.
>
> The httpd access_log shows an error 500, and the httpd
> error_log shows the following,
> [Wed May 17 20:17:47 2006] [error]
> Apache2::RequestIO::read: (70007) The timeout
> specified has expired at (eval 178) line 5
>
> Even if the problem is originating with these clients'
> proxy/firewall, it should never result the
> timeout/hanging of the CGI.pm. Does anyone have a
> suggestion on how to trace this or trouble-shoot it
> further?
>
> Apache/httpd 2.2.2
> Mod_Perl 2.0.2 (problem occurs with/without mod_perl)
> CGI.pm 3.20
> Apache2::RequestIO 2.000002
> Linux FC3: 2.6.12-1.1381_FC3smp
> Perl 5.8.5
> Client: IE6
> One client's proxy sets environment variable
> HTTP_VIA="1.0 WEBSENSE01SA, 1.0 Symantec_Web_Security
> (3.0.0.52)"
>
> Any suggestions/experience would be greatly
> appreciated,
> Tom
>
>
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