Dai un'occhiata qui:
http://msdn.microsoft.com/en-us/libr...b6(VS.71).aspx
e qui:
http://msdn.microsoft.com/en-us/libr..._predir_rename

da quel che ho capito si usa così.

#import <activex.dll> rename("auto", "auto_t")

oppure

#import <activex.dll> \
rename("auto", "auto_t")

Edit:

auto_rename

When importing a type library that uses one or more C++ reserved words (keywords or macros) as variable names, the auto_rename attribute renames these reserved words by appending two underscores (__) to the variable name to resolve potential name conflicts.