Mixer settings (mute/solo/etc...) aren't saved when closing score

Hi,
Musescore 1.2 rev5470 kubuntu 11.10 (with kde4.8)
I submit a bug that could sound like a feature request so I let you decide to move or not this in the appropriate section.
For example, I write a score with 3 staves. I want to ear only 2 staves together so I open the mixer, mute the third staff and click play. Everything is working great.
Now I want to save this mixer setting, it appears I can't do this. And If I close the score, when I open again the score, every staves are unmutted and I have to open the mixer and click on mute on the third again.
That seems not really annoying, but when you have about a dozen of staves, it's really laborious to have to click on mute on every staves you've mutted last time before working back.
So is there any way at this point of musescore developpment to do this?