this is our setup like:
zimbra mta(MX) --> antivirus --> zimbra mta --> mailbox
Our issue is Zimbra MTA will split the emails
e.g. if mailbox is forwarded to yahoo, email will be split/divided/duplicated to the mailbox and the yahoo
our issue now is yahoo received 2 emails because the email is duplicated/split twice, on both MTAs.
Any solution for this? How to turn off this on MX (first MTA) ??