I won't open another thread for this but I get 502 errors at home when trying to sync OmniFocus 1.1 (v.188.8.131.52348) on my MBP to my WebDAV server which is on a 10.4.11 G5/Quad workstation.
I'm using http rather than https (I'm on my own NATed net).
(Was I too eager when buying OF for my iPhone, the other day hoping that WebDAV sync would work?)
[FYI: MobileMe, Bingodisk or any other foreign service is an option]
When I was experimenting with HTTP (local network, not a hotspot obviously), I had to delete the database on the iTouch, then resync, then it worked. Sometimes it'd fail, but if I tried again, it'd work again.