Sorry, I was quoting "Offline" from the MS KB article (291617).

What I want to do is schedule the resource and have it automatically
accept and the event appear in the resource's calendar.

It turned out that the reason it wasn't working was that I needed to
set the type on the Recipient to olResource (had to set it to 3 as I'm
in vbscript).

Now I'm exploring the issue that the resource gets a different subject
on its calendar than the one on the original calendar!

Thanks,
Tim