NavMesh and Terrain: Path goes through hills

Hello,

i am using the NavMesh System from Unity and everything works fine until it gets to hills on terrains. Lets say i have a Agent standing in front of hill and he wants on the other side of it with the same height in the end. The hill is walkable so the obvious way is going up the hill and walking down again. That is what is happening eventually BUT the path i get is just two points: the start and the end. I dont get extra path corners on the slope of the hill or a t least on the top. The Path goes right throught the hill as if it wouldn't be there. But i really need those extra points, because i want to visualize the path (not going right through the hill) and i want to calculate the exact distance, which is obviously longer with the hill.

Any hints?

Best Regards chef_Seppel