problem libc6(2.3.1-[67]) + qmail

[Tomoaki Ishikawa (Home Address) <tomoaki@tomseye.net>]

I have a problem with libc6 version 2.3.1-6 that did not exist in the previous 
version.

When it changes after the version 2.3.1-6 of libc6, qmail does not operate.
A setup of qmail is completely the same.

The result accessed by 2.3.1-[6,7] of libc6 is as follows.
$ telnet localhost 25
 Trying 127.0.0.1...
 Connected to localhost.
 Escape character is '^]'.
 421 unable to read controls (#4.3.0)
 Connection closed by foreign host.

The result accessed by 2.3.1-5 of libc6 is as follows.
$ telnet localhost 25
 Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
220 tomseye.net ESMTP