Yeah it's primarily only for these types of extenders...
The Author who has transfered/abandoned the project (no updates even by the transfered to person since 2002) Although the sourcecode is included with the .zip file. If anybody wish to take a challenge.
About DOS32A found in Readme.txt after the preface from the author:
1.0 - About DOS/32 Advanced DOS Extender
DOS/32 Advanced DOS Extender is a state-of-the-art,
high-performance, high-speed, true "Plug&Play" replacement of the
world's most popular DOS Extender, DOS/4GW, created by Tenberry Software
(formerly Rational Systems Inc.) for WATCOM C/C++ and FORTRAN 77
compilers which allow DOS Extended applications to run in a 32-bit flat
protected mode environment.
DOS/32 Advanced DOS Extender provides full compatibility with WATCOM
C/C++ and features one of the most complete software emulations of
DOS/4GW, thus allowing the users to "plug" DOS/32 Advanced into the
protected mode programs which use DOS/4G, DOS/4GW, DOS/4GW Professional
and any other compatible DOS Extenders without the need to modify a
single line of code.
DOS/32 Advanced has been designed and optimized to be the fastest,
most flexible and highly compatible with other software DOS Extender. It
performs mode translating operations, such as Protected to Real and Real
To Protected mode switching, as fast as machine's hardware allow, and
while being compatible with DOS/4GW, it is the fastest DOS Extender that
supports WATCOM C/C++ at this time! A large number of configuration
options allow DOS/32 Advanced to be configured in hundreds different
ways, either by a special environment variable or by an external setup
program, giving its users the ability to manually adjust the number of
allocated selectors, callbacks, virtual stacks, turn off the exception
handling, change the size of DOS transfer buffer and much, much more.
Compatibility with "Clean" (also known as "Raw" or INT 15h), XMS, VCPI
and DPMI system softwares allows DOS/32 Advanced DOS Extender to run on
different machines with various operating systems installed.
Additionally, availability of such features as Null-Pointer Protection,
Extended Memory Blocks Checking and support for built-in Debug Mode
turns DOS/32 Advanced into a powerful tool for protected mode
programmers who want to make their 32-bit protected mode applications
Bolded some parts... This piece of code just sounds utterly amazing.
Helping Debug DOSBox.