Material properties reseting to default

Hi, I'm having some problems with some materials reseting when i save my project in unity 3.3. I edit my material changing some properties, and when i click in the save all option in unity, all the materials with that shader have some properties changed again to the default value. Somebody know anything about this problem?

Thanks in advance.

I stumbled upon this issue a few times. Usually the trick is to simply Reimport the shader and after that it's fine.