I think I saw same news somewhere in forum. Schalke 04 needed some good players in their squad. They are struggling right now both defensively and attacking wise but seems like these transfers would probably plug some holes for the moment. I still feel that they don't need someone old like Huntelaar. Doesn't feels like a good solution, though would work out for a while but feels like it would be same afterwards.
Well he scored still a lot at Ajax since his return. He can be the player they need to get some more goals.
He knows Schalke well so he doesn't need much time to get known to the club. Maybe even some old teammates are still playing there. Haven't checked that yet.