Mixing 32 and 16 bit indices in a VBO

[knackered]

Is there something I should know about mixing 32 and 16 bit indices within the same GL_ELEMENT_ARRAY_BUFFER?
I'm using subdata to place the blocks, and I'm aligning the start position of each block of indices to 32bit boundaries.
Anything else? My app (in fact, the whole of XP) is hanging in NVOGLNT when I enable mixed mode.

[knackered]

Ok, forget I said anything. I had a bug in my alignment code. So aligning blocks to 32 bit boundaries is all that's required.