Related Resources

It is worth seeing how others have accomplished
or thought about similar tasks.

Within OASIS, I know vaguely of two
similar efforts:

The OASIS XSLT Conformance TC (now closed)
that created a test suite for the W3C's XSLT Recommendation (http://www.oasis-open.org/committees/tc_home.php?wg_abbrev=xslt)

The ebXML Implementation, Interoperability
and Conformance (IIC) TC (http://www.oasis-open.org/committees/tc_home.php?wg_abbrev=ebxml-iic)

There are some interesting documents
at the W3C as well that indicate some best practices:

Variability in Specifications:  http://www.w3.org/TR/spec-variability/

Conformance Testing and Certification
Model for W3C Specifications:  http://www.w3.org/QA/2002/01/Note-qa-certif-20020102.html

-Rob