>Oh... I thought the capability to field more than one request simultaneously was apartment model threading (in and of itself).

Not exactly. DLLs that fit into the Apartment threading model are considered "aparmtent aware" and can be placed in the same MTS package with other components of the same model. VFP servers fit into this model. You can see for yourself by compiling a VFP server (in 6.0) and looking at its Registry setting under
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{yourguidhere}\InProcServer32

and looking at the value of the "ThreadingModel" key. Sure enough, its "Apartment"

So you can use VFP servers in MTS as apartment aware servers, it's just that when it comes down to business, they don't play right yet. They block concurrent calls.