[xml2rfc] cross-referenceing sections in external docs ?

[gmj at pobox.com (George Jones)]

Is there a way in xml2rfc to reference section numbers in other
documents ?

Currently, I've got

  "<t>Limit Sources of Management (<xreftarget="I-D.foo" />, Section 2.8.2)</t>

I'd like not to have to manually update section numbers in
cross-document references.

I've done some cpp-like things to XML in the past before feeding
to xml2rfc, but I'd like a better (native) solution.

Clues ?

Thanks,
---George Jones