Does anyone have a clue about this? Other toolsets, including gcc-2.95.3, gcc-3.3.3, and gcc-4.0.0 all work fine. "/usr/local/gcc-3.4.4/bin/g++.exe" -Wall -ftemplate-depth-100 -O0 -fno-inline -g -DBOOST_ALL_NO_LIB=1 -I"..\..\.." -c -o "..\..\..\bin.v2\libs\parameter\test\sfinae.test\gcc-3.4.4\debug\sfinae.o" "sfinae.cpp" "/usr/local/gcc-3.4.4/bin/g++.exe" -o "..\..\..\bin.v2\libs\parameter\test\sfinae.test\gcc-3.4.4\debug\sfinae.exe" "..\..\..\bin.v2\libs\parameter\test\sfinae.test\gcc-3.4.4\debug\sfinae.o" -g /usr/lib/gcc/i686-pc-cygwin/3.4.4/libstdc++.a(eh_terminate.o):: undefined reference to `___w32_sharedptr_terminate' /usr/lib/gcc/i686-pc-cygwin/3.4.4/libstdc++.a(eh_terminate.o):: undefined reference to `___w32_sharedptr_terminate' /usr/lib/gcc/i686-pc-cygwin/3.4.4/libstdc++.a(eh_terminate.o):: undefined reference to `___w32_sharedptr_unexpected' /usr/lib/gcc/i686-pc-cygwin/3.4.4/libstdc++.a(eh_terminate.o):: undefined reference to `___w32_sharedptr_terminate' /usr/lib/gcc/i686-pc-cygwin/3.4.4/libstdc++.a(eh_terminate.o):: undefined reference to `___w32_sharedptr_terminate' /usr/lib/gcc/i686-pc-cygwin/3.4.4/libstdc++.a(eh_terminate.o):: undefined reference to `___w32_sharedptr_unexpected' /usr/lib/gcc/i686-pc-cygwin/3.4.4/libstdc++.a(eh_throw.o):: undefined reference to `___w32_sharedptr_unexpected' /usr/lib/gcc/i686-pc-cygwin/3.4.4/libstdc++.a(eh_throw.o):: undefined reference to `___w32_sharedptr_terminate' collect2: ld returned 1 exit status -- Dave Abrahams Boost Consulting www.boost-consulting.com