Incorrect note lengths in playback when there's more than one voice in a staff

Greetings. I'm using version 1.2, WinXP.

My problem is that if there is more than one voice in a staff and they play the same note at the same time, but one plays it for longer than the other, Musescore's playback will only play the shorter duration.

For example, if one voice plays a C for the duration of a half note, while the other plays C for a quarter note and then moves to an E, playback will make it sound like ONLY the E is playing in the second quarter beat.

I have taken to replacing the shorter note durations with rests when I save the MIDI file, but this is a nuisance and I wonder if there's a fix for this or if any is planned.

Obviously, this is only audible with instruments that have sound for the duration of the note, so if you just use the piano it's unnoticeable.