Comment Re:Maybe selection bias (Score 1) 383
As long as you can control basic DNS records for your domain (GoDaddy even lets you do that) you can set the MX record for the domain to be the Dynamic DNS address and the whole thing should work just fine.
I've never actually tested it, but it sounds like it would work in theory.
DNS RFCs **require** that your MX records refer to IP addresses, not A or CNAME, which you'd get via a Dynamic DNS service.
I don't recall which RFC(s) at the moment, sorry.