Subsurface shadows not working with directional light?

I don’t know if I’m using the right terms, but If you look at the pictures below, it should make sense. I want my foliage with subsurface properties to be affected by shadows. For example, when there is light projected at a leaf, from behind it you should see the subsurface color. However, if there is an object between the leaf and the light source, casting the leaf in shadow, you shouldn’t see any subsurface coloring. For a while, I thought that perhaps UE4 just didn’t have that feature, because all of my foliage in shaded areas would still have lit-up backsides. But then I read something about the issue having to do with what type of light you’re using, so I switched on a point light, and voila(!), it worked. But I cannot get it to work with a directional light (what I’m trying to do is pointless without that type of light), and whenever I try to search for a solution, I can’t find any information. Help please? What am I missing?

Here’s what I DO NOT want, as it looks obviously wrong. This is using a directional light:

Here’s what I DO want, but it’s a point light, and I need a directional light to do this:

Any help on this? I’ve been stumped for quite some time, and googling the issue is just not returning a solution or answer.

Still no luck finding a solution. Is it a lost cause to hope someone can help me with this? Even if someone can just tell me it’s not possible, that’d be something.

bump - have you had any success with this yet?

Does anyone have a solution?