libqtdbus.so.4 error for jack

[P5music]

hi
I have jack installed and I see the "jack" picture on the application bar.
When I click on that picture nothing happens.
If I open the console and write qjackctl it loads but an error occurs about
libqtdbus.so.4
like it is not found
can you help me finding out?
thanks in advance

[Juanito]

That lib is in the qt-4.5-dbus extension - if you loaded the qjackctl extension using the appbrowser, it should have loaded the qt-4.5-dbus extension automatically since  it is listed in the dep file.