Problemer med at modtage mail - FLow Control error

Jeg sidder med et problem med at modtage mail pga. Flow Control error.
Vi har flere afdelinger rundt om i verdenen og vores afdeling i England, kan ikke sende mail til os.
Ved at køre en smtpdiag får vi følgende fejl:


C:\SmtpDiag>smtpdiag xx@xxx.com xx@xxx.dk /v

Searching for Exchange external DNS settings.
Computer name is XX-GN6971J.

Checking SOA for xxxxx.dk.
Checking external DNS servers.
Checking internal DNS servers.

Checking TCP/UDP SOA serial number using DNS server [10.0.0.2].
TCP test succeeded.
UDP test succeeded.
Serial number: 2008010401
SOA serial number match: Passed.

Checking local domain records.
Starting TCP and UDP DNS queries for the local domain. This test will try to
validate that DNS is set up correctly for inbound mail. This test can fail for
3 reasons.
    1) Local domain is not set up in DNS. Inbound mail cannot be routed to
local mailboxes.
    2) Firewall blocks TCP/UDP DNS queries. This will not affect inbound mail,
but will affect outbound mail.
    3) Internal DNS is unaware of external DNS settings. This is a valid
configuration for certain topologies.
Checking MX records using TCP: xxxxx.dk.
  MX:    mx1.mailfilter.mailoption.dk (10)
  MX:    mx2.mailfilter.mailoption.dk (20)
  MX:    mx3.mailfilter.mailoption.dk (30)
  A:    mx1.mailfilter.mailoption.dk [195.242.120.10]
  A:    mx2.mailfilter.mailoption.dk [89.104.216.10]
  A:    mx3.mailfilter.mailoption.dk [195.242.120.10]
Checking MX records using UDP: xxxxx.dk.
  MX:    mx2.mailfilter.mailoption.dk (20)
  MX:    mx3.mailfilter.mailoption.dk (30)
  MX:    mx1.mailfilter.mailoption.dk (10)
  A:    mx2.mailfilter.mailoption.dk [89.104.216.10]
  A:    mx3.mailfilter.mailoption.dk [195.242.120.10]
  A:    mx1.mailfilter.mailoption.dk [195.242.120.10]
Both TCP and UDP queries succeeded. Local DNS test passed.

Checking remote domain records.
Starting TCP and UDP DNS queries for the remote domain. This test will try to
validate that DNS is set up correctly for outbound mail. This test can fail for
3 reasons.
    1) Firewall blocks TCP/UDP queries which will block outbound mail. Windows
2000/NT Server requires TCP DNS queries. Windows Server 2003 will use UDP
queries first, then fall back to TCP queries.
    2) Internal DNS does not know how to query external domains. You must
either use an external DNS server or configure DNS server to query external
domains.
    3) Remote domain does not exist. Failure is expected.
Checking MX records using TCP: xxxxx.dk.
  MX:    mx3.mailfilter.mailoption.dk (30)
  MX:    mx1.mailfilter.mailoption.dk (10)
  MX:    mx2.mailfilter.mailoption.dk (20)
  A:    mx3.mailfilter.mailoption.dk [195.242.120.10]
  A:    mx1.mailfilter.mailoption.dk [195.242.120.10]
  A:    mx2.mailfilter.mailoption.dk [89.104.216.10]
Checking MX records using UDP: xxxxx.dk.
  MX:    mx1.mailfilter.mailoption.dk (10)
  MX:    mx2.mailfilter.mailoption.dk (20)
  MX:    mx3.mailfilter.mailoption.dk (30)
Both TCP and UDP queries succeeded. Remote DNS test passed.

Checking MX servers listed for xx@xxxxx.dk.
Connecting to mx1.mailfilter.mailoption.dk [195.242.120.10] on port 25.
Received:
220 Comendo Mailfence v.4.0 Ready!

Sent:
ehlo xxxxx.dk

Received:
250-reciever4.comendo.dk
250-PIPELINING
250-SIZE 104857600
250-VRFY
250-ETRN
250 8BITMIME


Sent:
mail from: <xx@xxx.com>

Received:
250 Ok

Sent:
rcpt to: <xx@xxx.dk>

Received:
450 <xx@xxx.dk>: Recipient address rejected: Recipient is protected by Flow C
ontrol -  Please try later.


Error: Expected "250". Server rejected the recipient address.
Failed to submit mail to mx1.mailfilter.mailoption.dk.
Connecting to mx2.mailfilter.mailoption.dk [89.104.216.10] on port 25.
Received:
220 Comendo Mailfence v.4.0 Ready!

Sent:
ehlo xxxxx.dk

Received:
250-reciever4.comendo.dk
250-PIPELINING
250-SIZE 104857600
250-VRFY
250-ETRN
250 8BITMIME


Sent:
mail from: <xx@xxx.com>

Received:
250 Ok

Sent:
rcpt to: <xx@xxx.dk>

Received:
450 <xx@xxx.dk>: Recipient address rejected: Recipient is protected by Flow C
ontrol -  Please try later.


Error: Expected "250". Server rejected the recipient address.
Failed to submit mail to mx2.mailfilter.mailoption.dk.
Connecting to mx3.mailfilter.mailoption.dk [195.242.120.10] on port 25.
Received:
220 Comendo Mailfence v.4.0 Ready!

Sent:
ehlo xxx.dk

Received:
250-reciever7.comendo.dk
250-PIPELINING
250-SIZE 104857600
250-VRFY
250-ETRN
250 8BITMIME


Sent:
mail from: <xx@xxx.com>

Received:
250 Ok

Sent:
rcpt to: <xx@xxx.dk>

Received:
450 <xx@xxx.dk>: Recipient address rejected: Recipient is protected by Flow C
ontrol -  Please try later.


Error: Expected "250". Server rejected the recipient address.
Failed to submit mail to mx3.mailfilter.mailoption.dk.

C:\SmtpDiag>

Fejl: Recipient is protected by Flow Control -  Please try later.

Jeg har søgt på nettet, men har ikke kunnet finde nogen løsning, så jeg håbede lidt på der var en eller flere kloge hovedet som lige havde svaret på dette?
Hvad kan det skyldes og hvad er løsningen på dette?
TDC er på opgaven også, men hidtil ikke hørt noget fra dem.

Pft :D