Well, in a few days mainstream end of support for Visual C++ 6.0 will end.  There is extended support thru 9/2005, but if you are an ISV using nmake to cross-compile your libraries and maintain some sort of code parity with your windows version.  Have a look at SFU or ping me if you need assistance moving to VC++ 7.1. 

 http://support.microsoft.com/default.aspx?scid=fh;[ln];LifeDevToolFam 

PRODUCT NAME

 MAINSTREAM SUPPORT EXPIRES

EXTENDED SUPPORT EXPIRES

Visual C++ 6

30-Sep-2004

30-Sep-2005

Here is a link to SFU:

http://www.microsoft.com/windows/sfu/default.asp