This is a follow-on from a previous post from which jjmck helped and appeared to solve.
The problem was with my SMTP banner not matching a reverse DNS. That problem appears fixed, BUT the messages that are in the server queue continue to "retry" without sending. Am I being impatient since it has only been about 1.5 hours? Even new msgs sent to the "retrying" domains are sitting in queue.
Thanks again for your help.