Navmesh Path is shown even between disconnected regions.?

I have taken a sample scene to describe my problem here. I have simply created 2 disconnected regions and my source point is in first region(bigger cube) and destination point is in second region(smaller cube). actually due to wall in between I should not get path between these two points. but when I call navmeshagent.calculatepath, I still get a path between these and also I get navmeshagent.pathStatus true. have I missed anything. thanks in advance.