Hello world compile error with stlport and Digital Mars - c++

Question

I'm jumping into C++ and I've fallen at the first hurdle.
I've got a simple hello world:
// #include <iostream>
int main()
{
// std::cout <<"This actually works!" << std::endl;
return 0;
}
I can compile this with Digital Mars using
\dm\bin\dmc hello
However, if I uncomment the two lines and try to get the iostream to work with
\dm\bin\dmc hello -I\dm\stlport\stlport I get the following error:
template <int _Is> struct __bool2type {
^
\dm\stlport\stlport\stl/type_traits.h(68) : Error: '=', ';' or ',' expected
};
^
\dm\stlport\stlport\stl/type_traits.h(70) : Error: identifier or '( declarator )' expected
_STLP_TEMPLATE_NULL
^
\dm\stlport\stlport\stl/type_traits.h(72) : Error: '=', ';' or ',' expected
struct __bool2type<1> { typedef __true_type _Ret; };
^
\dm\stlport\stlport\stl/type_traits.h(73) : Error: identifier or '( declarator )' expected
_STLP_TEMPLATE_NULL
^
\dm\stlport\stlport\stl/type_traits.h(75) : Error: '=', ';' or ',' expected
Fatal error: too many errors
--- errorlevel 1`
I've put the extra stlport folder in dm\stlport\stlport
My SC.INI is as follows:
[Version]
version=7.51 Build 020
[Environment]
PATH=%PATH%;"%#P%\..\bin"
BIN="%#P%\..\bin"
INCLUDE="%#P%\..\stlport\stlport";"%#P%\..\include";"%#P%\..\mfc\include";%INCLUDE%
LIB="%#P%\..\lib";"%#P%\..\mfc\lib";%LIB%
HELP="%#P%\..\help"