Copy and Paste operation results in corruption of voice 2

MuseScore 1.1 - XP Pro SP3

Just run across this one. The inline pics tell the story:-

First of all select the notes to copy:

Next fix the paste point

Notice the minim rest in voice 2 superimposed on the crotchet rest from voice 1

Now hit paste

The rest in Voice 2 remains a minim despite the pasted crotchet at the end of the bar. I have moved it down so it can be seen clearly.

I was able to repeat this several times.

I have attached the source file.

Is this a known bug? Or should I file an issue?

Regards
Michael