Typically when setting up a mail server, I create an rDNS record for the mail server IP to match the mail server hostname (ex: mail.example.com).
Can I instead set the rDNS ptr to match the parent domain (e.g. example.com), if this server is being used for multiple purposes, and still send mail successfully (i.e. not be classified as spam b/c of mismatched rDNS)?
EDIT: The article at http://en.wikipedia.org/wiki/Forward_Confirmed_reverse_DNS seems to indicate that it might be more complicated than I had thought. For instance, 1) I did not know that you could have multiple PTR records for a given IP; 2) it appears that as long as each PTR record matches an A record, everything is good (basically nullifying my question). Would you agree?