Self-shadows on clothing meshes

[Septfox]

'lo guys.

 

I've been messing around in Oblivion more lately, and since I have video hardware that can more than handle it, I have all the settings on and cranked up; including self shadowing.

 

I've noticed though, that on certain meshes my character's body and clothing doesn't cast shadows. This is mainly on meshes I've created or edited in 3ds myself, but a couple third-party ones have exhibited this behavior as well. Simple ambient "shadowing" is working fine, but actual self-shadows don't at all.

Well, I guess the easiest way to explain it would be to show you:

http://i1192.photobucket.com/albums/aa336/septfox/ScreenShot10.png

 

This is puzzling, because I've made small edits to the shirt, yet it's perfectly fine, whereas nothing else is casting or receiving shadows. The skirt is from another outfit, the rest of which I snipped off; I did try out the original mesh, and it was exhibiting the same issue.

And yes, stripes. I had stripes on the brain when I made this outfit months ago. *shrugs*

 

 

Is there some obscure flag in Nifskope that I've missed which enables a mesh to cast shadows/have shadows cast on it?