asterisk users - Jun 2005 - APP - ValetParking on CVS-HEAD -- instructions on its use, anyone?

I've finally got this beast installed, but now I don't see how to use
it.
I've looked over the web near and far, and it just seems that no one has
anything on its implementation.. This is all I get from the CLI:

*CLI> 
  -= Info about application 'ValetParking' =- 

[Synopsis]
Valet Parking

[Description]
ValetParking(<exten>|<lotname>|<timeout>[|<return_ext>][|<return_pri>][|<ret
urn_context>])
Auto-Sense Valet Parking: if <exten> is not occupied, park it, if it is
already parked, bridge to it.


I can guess that everything after 'timeout' is optional because of the
brackets, but I'm confused on everything else.  What is the 'exten'?
I was
under the impression that it was auto-generating on this particular app.  I
have no idea what 'lotname' is, but I feel that there should maybe be
some
lines added to features.conf for this thing?  Just no docs to tell me what
to do next.

Help, anybody?  I'd love some real-dialplan working examples...

Desparately yours,

Chris Coulthurst
chris@shuksan.com