The main thing is they are universal (if you have a mailer of a browser you
will need this functionality somewhere). Because they are universal their
syntax is understood communally. We need something with those properties
for XML. Then the problem disappears...
P.
Peter Murray-Rust, Director Virtual School of Molecular Sciences, domestic
net connection
VSMS http://www.nottingham.ac.uk/vsms, Virtual Hyperglossary
http://www.venus.co.uk/vhg