Naturals in key signatures display on all systems rather than just at point of change

Ubuntu Studio 14.04, GIT commit: 0826e2e

Reported in http://musescore.org/en/node/26761

1) new score for flute, 100 measures, D major
2) Style / General / Accidentals, "After.change ..."
3) Drag F major key signature to somewhere in the middle of the first system

Result: naturals appear at the key change (correct), but also on all subsequent systems (incorrect)