tremolos: up/down

I'm not sure if this counts as a bug:

Tremolos (on a single note) on voices (in a score where there are multiple voices per stave) orientate themselves as if there were no other voices on the stave. One can manually change the direction of the tremolo if it is on a 'stemmed' note (using X, e.g. on a crotchet or minim) - but not if it is on a semibreve or breve. This is difficult when writing for multiple voices.

MuseScore V. 1.1
Windows 7