For quite a few years the Visual C++ environment variable
MSVCDIR has served the role of MSVCNT (it is used by version
VC++ 6.0, first released in 1998).
Setting MSVCNT to the value of MSVCDIR is enough to get
Jambase working. It appears that Microsoft simply changed the
name of the variable.
This change makes Jambase look for MSVCDIR as well as MSVCNT.