JJ OS upgrade

yo
i got jjos 4.99 on the mp
if i wanna upgrade to the 2xl
i got no password fot the 4.99 since i bought the mpc from some one when 4.99 already was installed
does this cause any problems?

No, os2xl will ask you for a new password. Go to http://www7a.biglobe.ne.jp/~mpc1000/ and follow installation instruction.
Peace