Location of a XHTML+SMIL Profile schema

I was reading the XHTML + SMIL Profile Note [1] and cannot locate an 
implementation.

I have searched the web too and can't locate one.  Could someone please a) 
inform me where I could get one or b) inform me that there isn't such a 
schema available yet ?

Any form for the schema would be fine: DTD, XSD, Relax, ...

Thanks in advance,
Steve Speicher

[1] http://www.w3.org/TR/XHTMLplusSMIL/