Sunday, May 16, 2004

SMTP with t-mobile

Today I had to wait while I had a tire repaired, so I decided to wait at a Starbucks. I firgured that I would bring my laptop and use it to get some stuff done with the t-mobile 802.11b,

When I tried to send an email, my mail client stated that the mail server did not use authentication (The mail server that I use requires authentication). After a little digging, it looks like t-mobile intercepts all outgoing connections to port 25, and then sends it to their smtp server.

That seems like it could be a possible security concern. If I sent a message using the smtp server in my mail client (in general a isp or company’s server), and it actually goes to a different server, I don’t like that. I think that it would be better if they just blocked outgoing connections to port 25. Then the user should have to explicitly set up their smtp server in order to send outgoing messages.

I didn’t read the terms of service that closely, but this might be listed there.

Today, what I did was to tunnel the smpt connection through my ssh connection to the mail server. With doing that, I could guarantee the privacy of my email.


  1. frustrated with t-mobile blocking my smtpJune 29, 2005 at 2:40 AM

    how'd u do that?

  2. I have a server that I maintain, and I run an ssh server on it. On my mac, I run the following command line:
    ssh -C -X -c blowfish -L 8025:
    Once I have run this command, I configure my mail client to send mail with server "localhost" port 8025

  3. T-Mobile still intercepts and routes all SMTP traffic through they're servers, which are all listed on various spam-block lists right now because they're so poorly managed (I've been trying to get T-Mobile to pay attention and get them delisted for over a week).
    Your solution worked great - I had a Linux box at home that I was able to remote into (using VNC) and install openssh on. Once that was running, I got PuTTY up on my WinXP laptop here at the hotspot, setup the port forwarding, reconfigured Outlook to use the new ports and names and all's working great now.
    Thanks, Paul!

  4. I need the SMTP-Server of t-nobile. Do someone know it?

  5. I found what works for one, may not work for all.

    In my G1 I use the following settings for my POP accounts, on the domains I control.
    Using K-9 Mail

    Username: XXXXXXXXXXX
    POP Server:
    Port: 110
    No Security

    SMTP Server:
    Security Type: None
    Port: 25
    No Sign in required


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