>>Next: The 2 GB thing.

This might be something that might be better handled during the conversion to 64 bit, since you would have to check to ensure that the code was 64 bit clean anyway. The transition has be somewhat painful (from what I understand) for various flavours of Unix to convert to 64 bit, since it appears that many C programmers assumed that the size of a long is the same as the size of an integer, which is not true on a 64 bit machine. It might not be as big of an issue with Windows programs. Assuming I understanding this correctly:

Win16: Int (2 bytes) is smaller than long (4 bytes)
Win32: Int (4 bytes) is the same size as long (4 bytes)
Win64: Int (8 bytes) is bigger than long (4 bytes)

Kevin