SUMMARY
Technote 64 states the following:
Controls that support apartment-model threading should indicate this
capability in the registry, by adding the key ThreadingModel with a
value of Apartment under their class ID registry entry. To cause this
key to be automatically registered for your control, pass the
afxRegApartmentThreading flag in the sixth parameter to
AfxOleRegisterControlClass.
This information is not correct. Apartment-model threading is not supported
by MFC in Microsoft Visual C++ for Windows, version 4.1. The
afxRegApartmentThreading value is not used in this version and the registry
is not modified to reflect apartment-model threading support.
This documentation error was fixed in Visual C++ version 5.0. The following
text was added to Technote 64 in Visual C++ 5.0:
Note that apartment-model threading is only supported in Visual C++
versions 4.2 or later.