Compiling gzstream

I've been trying to create a compressed file reader similar to gzstream (http://www.cs.unc.edu/Research/compgeom/gzstream/). The problem is that I've not had a chance to use it because I can't get it to compile. The errors aren't in the source code but in the STL headers, specifically cerrno.h, cstdlib.h, and cstdio.h. The first few errors which occur are:

c:\Program Files\Microsoft Visual Studio .NET\Vc7\include\cerrno(16) : error C2143: syntax error : missing '{' before ':'
c:\Program Files\Microsoft Visual Studio .NET\Vc7\include\cerrno(16) : error C2059: syntax error : ':'

There are 204 errors, so I won't post them all! The above two errors appear in the following part of the cerrno.h header.

_STD_BEGIN
  #ifndef errno
using ::errno;   // <- Here
  #endif
_STD_END

I'm using MSVC++ 7.0, after just ditching 6.0 in hope of ridding myself of STL problems like this. Does anyone have a clue what the problem might be? The code isn't using any of the old '.h' headers (e.g. iostream.h), if this matters.