telnet localhost 25 freezes

[Zind]

On Thu, Nov 15, 2012 at 09:48:37AM +0000, thufir wrote:
> thufir at dur:~$ telnet localhost 25
> Trying 127.0.0.1...
> Connected to localhost.
> Escape character is '^]'.
> 
> 
> 
> and then I can't do anything.  Even the escape characters, carrot and 
> square-close-bracket don't exit that window.  
> 

carrot? What is this? carriage return?
(My mother tongue is not English.)

Well, just directly type `quit', then you can exit the telnet conversion
window.

An example to send e-mail using SMTP:
$telnet localhost 25
HELO localhost
mail from: <test1 at btest1.com>
rcpt to:<test2 at btest2.com>
data
/* message */
quit

P.S
I tried this(IIRC) several months ago, and this works.