Drum staff can not accept note input, but copy+paste works

My older installation mscore 0.9.5 (own build, TWM, SL5x)
did not accept input (mouse click) on drum-notation systems.
I had hoped this erroneous behaviour would disappear in v.1.0
I still can not enter notes - but I can make another system and assign drum sounds to that,
or copy+paste from another instrument into drum-system.

Way to reproduce:
New
add Drums
add Piano
C major
4/4
Start editing
Press N
Click on drum-staff - nothing happens.
File at http://d-axel.dk/pub/music/Hygge/Drummers_Dream.mscz
But the file does not show anything because I could not enter drum-notes :-)

I stopped using MINT's default windows-manager, it would not open a file-select menu
I changed window manager to IceWM - and then the select dialogue appears. MAYBE
this drum system behaviour stems from some other GUI error.

If you can enter notes in a Debian config then ignore this bug-report.
I am going to use Debian in a couple of weeks.

Thank you for a great program! Donald/Denmark.

Version of MuseScore I am using
version 1.0 revision 3996
ii libqtcore4 4:4.7.0-0ubuntu4.2 Qt 4 core module
ii libqtgui4 4:4.7.0-0ubuntu4.2 Qt 4 GUI module
ii libqtscript4-core 0.1.0-3ubuntu2 Qt Script bindings for the Qt 4 Core library
#cat /etc/debian_version
squeeze/sid
# cat /etc/issue
Linux Mint 10 Julia \n \l