Clef displayed incorrectly after change at beginning of system starting with mmrest

Ubuntu 14.04, GIT commit: 93e1d5b

1) new score for flute
2) enter whole notes in bars 5-32
3) press "M" to enable mmrests
4) click initial treble clef
5) double click alto clef in palette

Result: the original treble clef remains on the first system, with the alto clef only appearing on the second & subsequent systems. The note in bar 5 is displayed as if the alto clef *is* in effect, however. And if you toggle mmrests off, the alto clef is present in the "real" measure - it just isn't displaying properly in the mmrest.

This only seems to happen on the initial measure of a score. For instance, if after step 3 above I add a line break after bar 8, then delete the notes in bars 9-12 (thus converting them to a 4-bar mmrest), and then change the clef in bar 9 to alto, the change does take effect correctly. On the other hand, if I then undo, the notes return to their original positions, but the alto clef on this system remains. But again, if I then toggle mmrests off, the correct (treble) clef is seen.