<p>Our network admins have disabled IMAP and POP for our exchange server, but do have RDP over HTTP enabled.  Does Mac Mail only use IMAP to communicate with exchange servers, or does it also know how to use RDP over HTTP?</p>

For pragmatic use of RDF, Shelley Power's book
Practical RDF
is a good start.
The
ESW Wiki
is also a good resource
There's also
David Beckett's RDF Resource Guide
Tim Berners-Lee's notes
are always a good read
There's a
bunch of links
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