==== Required information ====
- iRedMail version (check /etc/iredmail-release): 0.9.0
- Linux/BSD distribution name and version: CentOS7
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx): Apache
- Manage mail accounts with iRedAdmin-Pro? Yes
- Related log if you're reporting an issue:
====

LOG:

Jul  8 04:20:38 mail postfix/smtpd[12278]: 0325963A9: reject: END-OF-MESSAGE from mail-la0-x229.google.com[2a00:1450:4010:c03::229]: 450 4.7.1 <END-OF-MESSAGE>: End-of-data rejected: Access denied; from=<EMAIL@gmail.com> to=<NAME@DESTINATIONEMAIL.com> proto=ESMTP helo=<mail-la0-x229.google.com>

====

names have been removed to protect the innocent.  Can anyone help me with this.  My client has @gmail.com in the whitelist, but I'm still getting this message in my logs, and they're not getting the email.  They've confirmed from the sender that they're getting a kick-back.

Are there any techniques I can try to get mail like this to go through?  The only think I can think of is that gmail (google) has been using IPV6 for everything, but my reverse DNS is updated and shouldn't be part of the issue.

thought?  Thanks for the help.