This is "Madara" when he freed the nine-tailed beast. This was fifteen years ago, let's call him Tobi.
This was "Madara" when he decided to help Itachi to destroy the village eight years later, let's simply call him Madara.
There's a significant difference between the two. The length and thickness of the hair. Here comes our first dilemma.
Tobi has Madara's eyes. Because Itachi implanted Sasuke's the Amaterasu jutsu to react on the sight of Madara's eyes.
Furthermore the resurrected Madara know of Nagato and the outer-path's ability to raise the living.
Furthermore we have this interesting pieces of dialogue.
Now Kakashi's statement is further enhanced by the fact that the Uchiha clan ancestor (the sage's child) didn't have the sage's eyes. Remember this was after he had fought the six paths of pain and witnessed the rinnegan firsthand.
Finally we have the eye of the ten-tailed beast which looked a bit more peculiar.