Intermittent port forwarding problems openssh 2.9.2p and up

[Gerardo Lamastra]

Hi,
 
I have configured ssh for port forwarding local 8080 to out company
web proxy server.

# ssh -L 8080:proxy:8080 myname at ssh-host
I've tried the configuration by using
# telnet localhost 8080
and it works fine. But whenever I try to use it with any http browser,
it just fails. 
I investigated the problem with Ethereal and I've noticed that packets
travel on loopback interface, arrive over ssh-host, but there only the
3-way handshake is performed and no extra data is sent to the proxy.
It's like data is "lost", and the proxy timeouts.

The same behavior happened using different ssh clients (openssh-2.9.9 on
Linux
and ttssh for Windows), different server (different release of openssh
(2.9 and 2.5 mainly) on different architectures (Linux & OpenBSD));
different web browsers (lynx, links,netscape, explorer). I've also tried
different proxy servers (netscape proxy server and squid)

I tried it with other protocols (Ex. using imap access to our corporate
mail hub) using Netscape and it seems to work fine.
This seems very similar to the problem reported by mcurtis9 at csc.com.au
on 2001-09-25 2:09:57.
Thanks for your attention.

--
Gerardo Lamastra
Centro Sicurezza Be-Secure
Telecom Italia LAB
Via Reiss Romoli 274 - 10148 Torino
Tel. 011 228-6586
Fax. 011 228-6360