Simpsons: Night of the Living Treehouse of Horror Cheats (GameBoy Color)

Enter the following codes at the Password screen (the Simpson's garage) to unlock the
corresponding levels: 
  Level 2 (Flying Tonight): JTWKYTQBBKW 
  Level 3 (Plan 9 From Outer Springfield): TNSLRYSJGWW 
  Level 4 (Vlad All Over): BXPGCFPYJWB 
  Level 5 (If I Only Had a Body): WSQJLTQFYWK NPKYGBKTFWQ 
  Level 6 (King Homer): XQRFJWRBTWP