[BB1877]

Mail sent from Lotus Notes client delivers to certain addresses okay. However mail sent by the same user from their BlackBerry is failing with a message from a couple (but not all) far-end mail servers:

SMTP Protocol Returned a Permanent Error 557 Your IP xx.xx.xx.xx does not have a reverse DNS entry. Disconnecting...

I have two BES in the same data center, and this only happens on one BES. A "What is my IP address" test from both BES reveals the SAME external IP address.

Does mail sent from BlackBerry thru BES appear externally different than mail sent from the mail client?

[x14]

This is not a BES issue. This is an SMTP issue.

Do you have a DNS reverse lookup record for your SMTP server?

Are you having this issue sending to the same email address in Lotus Notes and on the BlackBerry?

Do you have multiple SMTP server sending to external hosts?