Oops... I missed reading this thread... With "C:\MinGW\bin", or wherever you have the mingw gcc.exe, in your "PATH" doing:
echo %Path% cd \location\of\jam\src .\build.bat mingw
Produces for me: C:\DevRoots\Boost\boost\tools\jam\src>echo %Path% C:\Python24\.;c:\MinGW\bin;C:\WINNT\system32;C:\WINNT;C:\WINNT\System32\Wbem;C:\Program Files\Common Files\GTK\2.0\bin;C:\Boost\bin;C:\Boost\lib;C:\Pr ogram Files\PuTTY;C:\Program Files\Perforce;C:\Program Files\QuickTime\QTSystem\;C:\Perl\bin;C:\Program Files\GnuWin32\bin;C:\Program Files\doxygen\bi n;C:\Program Files\Common Files\Adobe\AGL;C:\Program Files\Subversion\bin;C:\Bin;C:\DevRoots\RSI\org\stlport\STLport\bin;C:\KDE\bin C:\DevRoots\Boost\boost\tools\jam\src>.\build.bat mingw ### ### Using 'mingw' toolset. ### C:\DevRoots\Boost\boost\tools\jam\src>rd /S /Q bootstrap C:\DevRoots\Boost\boost\tools\jam\src>md bootstrap C:\DevRoots\Boost\boost\tools\jam\src>gcc -DNT -o bootstrap\jam0.exe command.c compile.c debug.c execnt.c expand.c filent.c glob.c hash.c hdrmacro.c headers.c jam.c jambase.c jamgram.c lists.c make.c make1.c newstr.c option.c output.c parse.c pathunix.c regexp.c rules.c scan.c search.c subst.c time stamp.c variable.c modules.c strings.c filesys.c builtins.c pwd.c class.c w32_getreg.c native.c modules/set.c modules/path.c modules/regex.c modules/ property-set.c modules/sequence.c modules/order.c C:\DevRoots\Boost\boost\tools\jam\src>.\bootstrap\jam0 -f build.jam --toolset=mingw "--toolset-root= " clean ...found 1 target... ...updating 1 target... [DELETE] clean ...updated 1 target... C:\DevRoots\Boost\boost\tools\jam\src>.\bootstrap\jam0 -f build.jam --toolset=mingw "--toolset-root= " ...found 47 targets... ...updating 1 target... [COMPILE] bin.ntx86\bjam.exe ...updated 1 target... -- -- Grafik - Don't Assume Anything -- Redshift Software, Inc. - http://redshift-software.com -- rrivera/acm.org - grafik/redshift-software.com -- 102708583/icq - grafikrobot/aim - grafikrobot/yahoo