QUOTE(bben46 @ Apr 29 2008, 08:55 PM)

The D2D version cannot be patched or upgraded except from D2D. It's not Bethesda's fault. Everything at D2D is encrypted. The purpose is to keep people from making copies and passing them out to their friends. Unfortunately, they don't warn you ahead of time. they portray their version as 'Just like the one you buy in the store, but available right now if you have a credit card."
They do have patches available though I'm not sure if they have an SI patch or if they make you pay for it.
Just checked the D2D site, they say SI is not available for download - So I doubt if a patch is available either.
The SI expansion is available for download, that's where I got mine...