It means "see ya" as in "see ya later". Only it is a much cooler, down to the ground, bad to the bone way of saying it. "See ya" is lame, "see ja" has game. Accent the "ja" for ultra cool, gangsta emphasis.
Old cool Tony said "See ja, don't wanna be ja", as he drove off with his ladies in his low rider LD pimp mobile.
von RCA Man 28. November 2005