dont sound good to me,one of the selector forks may have a bend in it or possibly a circlip or snap ring has come off one of the shafts.either way its engine out and split in in half.it really needs to be looked at first take the clutch cover off and try selecting gears and you will see the selector shaft moving in there,there will be two pawls that move the selector drum around make sure they are both sprung out and doing their job.
adam bike doctor
February 2010