This can happen when no layer is selected, e.g. when pressing with move tool on any pixel on the background layer. It is observed on all photoshops, CS2 for example.
What version of photoshop?
Generally those options are grayed out if you don't have a shape layer already active.
I found the solution. I must be carefull not only to have the layer selected but also its mask.
When the mask is unselected the path features are NOT available.