Digital Satin Productions release Strip Blackjack 2 DS *Update 1*
Description from the readme:
This is an early build of SBJ2, considered a late prototype. As such, many functions are not yet working, and there may be a few bugs in the code. This game uses libfat so it requires a slot-1 card or appropriate DLDI patches for emulators.
You should be able to place sbj2.nds anywhere on your card, but the gamedata folder needs to be at root. I use a standard directory system for all my games, and they all start with "gamedata".