in your code file? Is this a new problem, or have you seen it with previous versions of VA? I have just tried a simple test here and I am not seeing any problems typing "UInt32" using VS2005 and VA 1647.
Turning off:
VA Options -> Advanced -> Correction -> Repair case
should stop the case correction problem, but it would be good to find and fix the underlying problem.
I just built this machine, so 1647 is the first version I've installed. Everything was working on my old machine, so I'm somewhat stumped, because there just isn't much on this machine right now. It's Vista x64, but I have another machine like it that does work properly.