We're developing a substantial backlog for MSN.com:

$ lscp show queue  /sum /dest=msn.com

SMTP entries:
-#Rcp. -#Msg ---Size--- MRt -Oldest msg-- ------------Destination--------------
  1489   374    1396323   0    0 03:18:01 MSN.COM
------ ----- ---------- --- ------------- -------------------------------------
  1489   374    1396323                   1 destination(s)

The following is consistent with what I'm seeing in the logs.  It looks
like a block to me, but I suppose they might just be broken.

$ lscp resolve /connect msn.com
15:21:04 MX query for MSN.COM
15:21:04 trying (via UDP) DNS server 149.68.16.12

status = %LSMTP-S-OK, Ok
cname = MSN.COM
mailers:
    smtp-gw-4.MSN.COM 20 207.46.181.13

15:21:04 connecting to smtp-gw-4.MSN.COM
15:21:04 error reading from network
15:21:04     status = %SYSTEM-F-LINKDISCON, network partner disconnected
                      logical link

                                                -Kary