[Mailman-Users] Postfix error

[Bob Puff@NLE]

Hey gang,

On a list that has been working flawlessly for 6 months, this morning it suddenly stopped.  I got an email from Postfix (2-28-2001 version) with:

Transcript of session follows.

 Out: 220 main.nlenet.net ESMTP Postfix
 In:  ehlo main.nlenet.net
 Out: 250-main.nlenet.net
 Out: 250-PIPELINING
 Out: 250-SIZE 10240000
 Out: 250-ETRN
 Out: 250 8BITMIME
 In:  mail FROM:<sac-admin at list.domain.com> size=2760
 Out: 250 Ok
 In:  rcpt TO:<user1 at home.com>
 Out: 250 Ok
(deleted lots of people)
 In:  rcpt TO:<luser110 at aol.com>
 Out: 250 Ok
 In:  data
 Out: 354 End data with <CR><LF>.<CR><LF>
 Out: 451 Error: queue file write error
 In:  rset
 Out: 250 Ok
 In:  quit
 Out: 221 Bye

No message was collected successfully.

I am running Mailman 2.0.1 on this particular list.  Checked the mailman logs, and just found that it couldn't deliver messages to postfix.  Checked the Postfix log, and really didn't find anything... I see where the messages came in, but nothing was sent out.  Checked the archives - no new messages.  Looked in the locks directory - aha, locks!  Deleted them, they came back the next minute.  Tried this a couple times, no go.
All the while Postfix was sending and receiving mail fine, including other Mailman lists (on a separate install).

After mailing myself a copy of my postfix log, I got a few more emails like the above, then bam, it kicked back in, delivering all the backed up mail!  Been working ok ever since.  

What happened???  I had plenty of space (and free inodes) on /var, which was the only thing I could come up with from looking at postfix.org.

Bob