People like me just don't want to support XML (full-blown as it
is) in DNS and MTA software at all.
Hear, hear. And I can understand why. However, you miss an important
point: What code developers want or do not want to do is irrelevant when
Microsoft is in the loop. SPFv1 is not enough to cut it, and SPFv2
without Meng does not stand a chance against Microsoft.
Thus, implementing and then hoping people won't publish
XML doesn't actually solve the problem.
Then code your implementation to ignore the XML part and deal only with
the "old style" syntax of SPFv2. People that would publish the XML part
are not stupid: if it's not in any implementation other than Microsoft's
they're not going to bother. That's one advantage of having two
different ways to do things.
Michel.