Tied unisons in two voices create incorrect accidentals in following notes

When two voices are in unison and tied over a bar line, and one of the voices then repeats that same note, then an incorrect accidental often appears.

For example, see attached picture, where two voices are playing C for one-and-a-half measures, then the top voice moves up while the lower voice repeats the C. The repeated note obviously should not have a natural sign.

I have tried this using 1.3 as well as the nightly build (2013-08-30).

As a workaround, I went through a score and made such accidentals invisible. Unfortunately, when reloading the file, the accidentals do not appear right away, but then get created when editing other parts of the score, and are thus no longer invisible.