Duplicate the last entered note

I am using MuseScore 1.3 on Mac OS X 10.9.2 (Mavericks).

After entering a g-flat another g-flat is required. I try this with the keyboard key "R" (duplicate the last entered note). Unfortunately MuseScore generates an f-sharp instead. Of course, in equal temperature tuning, they sound the same, but in my score the optical difference is essential.

Shouldn't MuseScore generate exactly the same note on using the "R" key?
Thanks for your response!

Robert