FPS Controller can jump over anything

Hi, No matter how steep a surface is my FPS Controller(unity 5.0.2) can jump over it.I have mountains who surrounds my map and some of them make almost 90 degrees with the ground.No problem for my olympic champion at jumping/climbing who makes it over them and out off the map.If i understood correctly from unity manual this setting is the "Slope Limit", but there they recommend a 90 degrees value, while the default setting is 45.Either way, except perfectly perpendicular walls, my FPS Controller can jump/climb over anything.How do i correct this behavior?Thanks!