How do I use using namespace System; with VS 2012 and Intel Composer XE 2013?

Simple question but I can't get a CLI mode program to work if I compile using Intel Composer XE.  I need to use Intel Composer XE for this project.

This is one of the error messages I get if I try to include the appropriate DLL.

#using <mscorlib.dll>

using namespace System;

etc..etc..

"#using" requires C++/CLI mode

And the option for CLI mode disappears in Properties/General if I select Intel as the compiler so that isn't helpful.

The program compiles fine if I use Visual Studio instead of Intel.  This IDE stuff really burns me at times.