> I was wondering if current MSVC compiler has a option to compile
> a 64-bit version. Probably would hardly have any effect on performance
> but perhaps on compatibility issues?

It doesn't, not the VC6 version I'm using (afaik).

I'm not sure how much work would be involved in converting it to 64
bit. 99% of the code would probably run without a problem, but that 1%
may take you ages because bugs may creep up that are not easily
traceable. You never know till you try though.

Dimitris