Policy on binary compatibility in kdesupport?

[Sebastian Trüg]

The problem is simple: I want to introduce transactions into Soprano. That 
will break BC since it introduces new virtual methods.
Now normally I would go about this by releasing Soprano 3 and increasing the 
lib version.
However, I don't know what the policy is here. Is this allowed at all? Or does 
kdesupport need to stay binary compatible until KDE 5?

Cheers,
Sebastian