In the current and former version of PalmOS, they've always had Windows based hardware (em|sim)ulators and a decent SDK (I used to develop software for old PalmOS 3.5 and 4.0). Natively, the languages they were written in were C and C++, though, there've been some scripting platforms written for PalmOS in the past.

With the new Palm WebOS, supposedly it's supposed to be Javascript, CSS, and HTML (though not sure how that translates into certain things like opening sockets and whatnot).

I've always been pretty impressed with Palm's Developer Network.