Transparency slider slow on Ubuntu (compared to Windows), workarounds?

I've used Inkscape 0.46 and 0.47(pre3 mostly) on Windows Vista and Windows 7 during the past few months (at work). I love the program!

Since I'm using Ubuntu at home, and I know Inkscape is a platform-independent program, I installed it there too.

But after a while, I noticed that the responsiveness of the Transparency slider (under Ctrl+Sh+F-dialog) is _very_slow_. It is so slow it becomes a hindrence of working with Inkscape under Ubuntu. After all, transparency is a very useful technique to draw shades and speculars.

As a semi-workaround to this, I've started typing in for example 50 and presssing Tab for the update to apply - instead of using the more natural mouse drag to pull down the transparency slider.

Also, sometimes the Sh+F6 tool feels bogged down to a crawl.

And I've turned down all filtering under preferences to the lowest possible - it does not help with the transparency slider, but of course speeds up the general zooming/panning responsiveness.

Does anybody have any hint/experience about this performance problem which seem related to linux systems?

Thanks for a great program!