Not sure what you mean but I have had a stopover within the US on an international award ticket. Haven't tried it within a foreign country though if that is what you mean.
Stopover can be in a country that's neither origin nor destination: FRA-ICN-MEL//SYD-KUL-LHR(stop)-AMS-FRA worked just fine for me. (Having a hard time convincing myself to fly the bit back to FRA since it's cheaper and faster to just fly where I want to go in Germany.)