tie after accidental creates wrong pitch note

Score in G major with a single staff for C trumpet. Input an eight note Bb tie to a quarter note. Instead of a Bb an A appears, tied to the Bb. Correct, save, close and reopen. The quarter note Bb has turned to a B natural. the eight note Bb ties to the next Bb in the score.

Ubuntu 9.04
MuseScore 0.9.5 1898