If John could explain what the problem is (he mentioned absolute paths, but Boost.Build doesn't really use absolute paths so I'm still a bit confused), maybe a small tweak could be applied to fix it up.
I don't think that a small tweak will be enough: bjam -sTOOLS=borland -d2 regex ...found 526 targets... ...updating 83 targets... MkDir1 ../libs/regex/build/bin/libboost_regex.a/borland mkdir ../libs/regex/build/bin/libboost_regex.a/borland MkDir1 ../libs/regex/build/bin/libboost_regex.a/borland/debug mkdir ../libs/regex/build/bin/libboost_regex.a/borland/debug MkDir1 ../libs/regex/build/bin/libboost_regex.a/borland/debug/runtime-link-dynamic mkdir ../libs/regex/build/bin/libboost_regex.a/borland/debug/runtime-link-dynamic borland-C++-action ../libs/regex/build/bin/libboost_regex.a/borland/debug/runtime-link-dynamic/ c_regex_traits.o "bcc32" -j5 -q -c -P -w -Ve -Vx -a8 -DBOOST_REGEX_NO_LIB=1 -DBOOST_REGEX_S TATIC_LINK=1 -v -Od -vi- -tWC -tWR -WC -WM- -w-8001 -I"../libs/regex/buil d" -I"/cygdrive/d/boost/develop/boost" -o"../libs/regex/build/bin/libboost _regex.a/borland/debug/runtime-link-dynamic/c_regex_traits.o" "../libs/regex/build/../src/c_regex_traits.cpp" ../libs/regex/build/../src/c_regex_traits.cpp: Error E2209 ../libs/regex/build/../src/c_regex_traits.cpp 25: Unable to open inc lude file 'boost/config.hpp' ...interrupted ...updated 3 targets... There are two issues here: the boost include path is always an absolute /cygdrive/d/.. path whatever I do with BOOST_ROOT, and the SUFOBJ SUFLIB etc are all set wrong. John Maddock http://ourworld.compuserve.com/homepages/john_maddock/index.htm