when coding i always test on hardware so ... i'm not so god with emu. Also nogba doesn't flip sprite wery well [when useing scale to flip].
Hope you like and download it despite the bad picture 8)
Here it's a thread library for the Nintendo DS.
http://donotjava.netsons.org/?page_id=67
If it get the right attention i've some more code to add [semaphore and condition_variable tnx nathaniel].