I'd like to go ahead and bump this by saying I actually found this via a Google search, which provided quite a smile.
In any case, in my situation I had installed W7 x64 to a VM and was using NotMyFault to generate all sorts of cool kernel-dumps for analysis. What was the problem?
00000000 00000000 00000000 00000000 00000000 0x0
The context is partially valid. Only x86 user-mode context is available.
The wow64exts extension must be loaded to access 32-bit state.
.load wow64exts will do this if you haven't loaded it already.
After installing the hotfix in VG's post, I got a complete dump : )
What I imagine was the problem was my VM OS was as basic as it gets. It was W7 x64 with WU disabled, therefore none of the updates and hotfixes were installed. Because of this, the only thing I can think of was this hotfix (or at least one like it) is installed when running WU, but since I didn't, I obviously didn't have the hotfix installed.