AE is somewhat lighter, i.e. it's missing some stuff from the desktop version. it also does some things automatically where the desktop version requires some extra method calls. Some classes have moved package also. If you take the AE-docs as reference and try to find the corresponding classes/methods in desktop jPCT, it shouldn't be too hard. However, this only applies to jPCT itself. It doesn't cover the application itself, listeners, mouse- and keyboard control...you have to hide these things behind some interfaces to make your code work on both platforms.
Personally, i don't think that it's worth it. Then again, i don't find developing directly on the device slow. It kinda was with my old Samsung I7500, but with the Nexus S, it's really fine IMHO.