[Dovecot] Disconnects with proxies / new facts

[Peter Fern]

Looks like a problem with the proxy to me - sending carriage returns
after each character.  You say 'as soon as the client uses some pop3
proxy,' but I wonder - have you actually tried another proxy, and have
you tried this one with other pop servers?  We know dovecot is working
since you've stated as much, and all dovecot does is interpret what's
sent to it over the socket...

Michael Kress wrote:
> Hi,
>
> I just tried the below with the current version 1.0 RC15 and I still
> got the Problem:
> telnet gives me the following output:
> -----8<-----8<-----8<-----SNIP-----8<-----8<-----8<-----
> +OK dovecot ready.u-ERR invalid command u
> s-ERR invalid command s
> e-ERR invalid command e
> r-ERR invalid command r
> -ERR invalid command
> u-ERR invalid command u
> s-ERR invalid command s
> e-ERR invalid command e
> r-ERR invalid command r
> _-ERR invalid command _
> 1-ERR invalid command 1
>
> -ERR invalid command
> -----8<-----8<-----8<-----SNIP-----8<-----8<-----8<-----
>
> The above output results from the following entry: user user_1[ENTER]
>
> So now I know that this is no version issue.
> Can you tell me something on how I can find the solution for this
> problem? I don't think its a firewall issue, I disabled my Desktop
> Firewall. On the server I use shorewall, but of course, port 110 is
> open and it works disabling AntiVir on the client side. The error also
> occurs when I disable the Server Firewall as well. The error is
> reproducible on several PCs (I tried 3 PCs).
> Have you got any hint? Without solving the problem, I have to switch
> the pop3 server to another one, because this problem is really a
> crucial one.The only problem is: I loke dovecot. :)
>
> Thanks in advance!
> Regards,
> Michael
>
>
> -------- Original-Nachricht --------
> Betreff:     [Dovecot] Disconnects with proxies
> Datum:     Wed, 06 Dec 2006 22:43:00 +0100
> Von:     Michael Kress <kress at hal.saar.de>
> An:     dovecot at dovecot.org
>
>
>
> Hi,
>
> I know I shouldn't ask stuff like this when using dovecot-0.99.11-4.EL4
> (CentOS-4.4), but why I'm asking this is whether it's worth to switch
> from rpm based upstream dovecot to a self compiled one or not and thus I
> think you wouldn't kill me presenting you this question. o:-)
>
> I've got a problem with dovecot regarding a pop3 proxy issue.
> When I configure my dovecot server to do just plain pop3 I can telnet
> from a windows box without any flaw, but as soon as the client uses some
> pop3 proxy (for example outlook uses avira antivir Mail-AntiVirus
> Protection), queries to that server fail. A log line looks like this:
>
> pop3-login: Dec 05 22:53:24 Info: Disconnected [::ffff:84.165.54.42]
>
> Moreover with the proxy activated, a telnet to port 110 (pop3) is not
> working properly, the cursor stays right behind "+OK dovecot ready." and
> as soon as I enter a character, the server rejects this character as an
> unknown command (Without pressing ENTER). As soon as I turn off the
> Antivir-Proxy the telnet to
> port 110 runs flawlessly and I can login.
>
> So I'd like to know is there anything I can do with this version or is
> it worth trying the newest version? Is this a known issue?
> Thanks in advance
>
> Michael
>