Re: Alternative to TXT or new RR

You know, if can give the receiver an SPF record to interpret, you can 
interpret that same data yourself. Therefore, RPC-to-publisher is at 
least as capable as SPF-like schemes.
And it's more powerful. For example, it's easy to tell receivers "no" if 
the localpart's not an allowed sender. The IBM situation described in a 
different thread seems easy to handle, too.
Arnt