was messing around with a sculpted chair in my house when I first noticed this but seems like when you put a sculpted object inside a hollowed out, semi transparent prim it goes somewhat transparent and anything between the sculpted prim and the hollowed one isn't textured right... if you look through the sculpted one (if that makes sense)
Seems that it only works if the sculpted prim has a somewhat light gray texture, though it strangely still works if you color it completely black, the hollowed prim can be anything as far as I know, just at long as it has a transparency of at least 2...
EDIT: ok so... a pic would be nice huh? I'll post one as soon as I find somewhere that won't screw up on me while uploading...