All right mantra, I looked into the program and the option is already there!

Just add this line to the [AAVM] section of your avast! 4 file:

NeverShowInfo=1

This will suppress all blue info boxes that avast produces.
However, I’m not sure if this is what you want as now it won’t tell you e.g. even when a new program update is ready…

Thanks
Vlk