Question : Session Timeout during Session

We are running MDaemon Pro 11 email server and we are having problems receiving emails from this one domain. This is the only domain we seem to be having problems receiving emails from. Below you will see the log of the transaction. To me it seems as though the sending server has stop transmitting data to our email server and the session stays open for the max time limit of 15 minutes and then our server terminates the session. Can anyone help shed some light into what is causing this problem. I feel the problem exists on the senders server and of course they say the problem exists on our server. I can watch all the other emails coming and going with no problems except for this domain.

Fri 2010-06-18 00:09:03: <-- MAIL FROM:<sherry@sendingdomain.com> SIZE=222850
Fri 2010-06-18 00:09:03: Performing IP lookup (outbound101.virtualconnect.net)
Fri 2010-06-18 00:09:04: *  D=outbound101.virtualconnect.net TTL=(60) A=[208.83.76.51]
Fri 2010-06-18 00:09:04: ---- End IP lookup results
Fri 2010-06-18 00:09:04: Performing IP lookup (sendingdomain.com)
Fri 2010-06-18 00:09:04: *  D=sendingdomain.com TTL=(120) A=[0.0.0.0]
Fri 2010-06-18 00:09:04: *  P=010 S=002 D=sendingdomain.com TTL=(44) MX=[sendingdomain.com.inbound10.mailprotector.net]
Fri 2010-06-18 00:09:04: *  P=020 S=003 D=sendingdomain.com TTL=(44) MX=[sendingdomain.com.inbound20.mailprotector.net]
Fri 2010-06-18 00:09:04: *  P=030 S=000 D=sendingdomain.com TTL=(44) MX=[sendingdomain.com.inbound30.mailprotector.net] {208.83.76.61}
Fri 2010-06-18 00:09:04: *  P=040 S=001 D=sendingdomain.com TTL=(44) MX=[sendingdomain.com.inbound40.mailprotector.net]
Fri 2010-06-18 00:09:04: *  D=sendingdomain.com TTL=(120) A=[0.0.0.0]
Fri 2010-06-18 00:09:04: *  D=sendingdomain.com TTL=(120) A=[0.0.0.0]
Fri 2010-06-18 00:09:04: *  D=sendingdomain.com TTL=(120) A=[0.0.0.0]
Fri 2010-06-18 00:09:04: ---- End IP lookup results
Fri 2010-06-18 00:09:04: Performing SPF lookup (sendingdomain.com / 1.1.1.1)
Fri 2010-06-18 00:09:04: *  Result: none; no SPF record in DNS
Fri 2010-06-18 00:09:04: ---- End SPF results
Fri 2010-06-18 00:09:04: --> 250 <[email protected]>, Sender ok
Fri 2010-06-18 00:09:04: <-- RCPT TO:<myuser@receivingdomain.com>
Fri 2010-06-18 00:09:04: Performing DNS-BL lookup (1.1.1.1 - connecting IP)
Fri 2010-06-18 00:09:04: *  bl.spamcop.net - passed
Fri 2010-06-18 00:09:04: *  zen.spamhaus.org - passed
Fri 2010-06-18 00:09:04: ---- End DNS-BL results
Fri 2010-06-18 00:09:04: --> 250 <[email protected]m>, Recipient ok
Fri 2010-06-18 00:09:04: <-- DATA
Fri 2010-06-18 00:09:04: Creating temp file (SMTP): f:\mdaemon\queues\temp\md50000011977.tmp
Fri 2010-06-18 00:09:04: --> 354 Enter mail, end with <CRLF>.<CRLF>
Fri 2010-06-18 00:28:21: Connection timed out!
Fri 2010-06-18 00:28:21: SMTP session terminated (Bytes in/out: 102704/356)
Fri 2010-06-18 00:28:21: ----------

Answer : Session Timeout during Session

The problem was resolved on the senders end. There was no issue on my end.