Right after Line 33 of "
Apparently, my Domino server blows up whenever a JSON file is requested with anything other than a "GET" command. Who know, eh? Either way, it works fine now. I don't know if you might have to do this with all tree panels, but I guess I'll find out as soon as I start workign with them again.
Now, a lot of these examples don't work on a stock Domino server, because they use PHP, but they work on the ExtJS.com site, if you need them.