Hi, I posted this a while ago but with no response, so I'm trying again. If anyone is using the boost::threads library with gcc & STLPort and has no problems, perhaps they could let me know - at least then I know its worth perservering with (or at least try compiling my example?) If I try to compile the example below with a makefile (also below), then I get this linker error: /home/ncain/tmp/ccaK5aes.o(.text+0x4b): In function `main': : undefined reference to `boost::thread::thread[in-charge](boost::function0<void, _STL::allocator<boost::function_base> > const&)' If I don't use the _STL namespace it compiles. Looking at the libboost libraries, they contain references to _STL stuff, so I assume I compiled them ok (bjam -sTOOLS=gcc-stlport -sBUILD="<stlport-iostream>on" ) Does anyone know what could be wrong? (or how I can change a bjam file to include the /usr/local/include/stlport path? so I could try that) nik testboost.cpp: #include <iostream> #include <boost/thread/thread.hpp> #include <boost/thread/xtime.hpp> using namespace _STL; struct thread_alarm { thread_alarm(int secs) : m_secs(secs) { } void operator()() { cout << "alarm sounded..." << endl; } int m_secs; }; int main(int argc, char* argv[]) { int secs = 5; thread_alarm alarm(secs); boost::thread thrd(alarm); thrd.join(); } Makefile: .PHONY: all clean ALL = testboost LIBS= -I/usr/local/include/stlport -I/home/ncain/boost_1_31_0 -L/usr/local/lib -lstlport_gcc -lboost_thread-gcc-mt-gdp .cpp: ${CXX} -lpthread -o $@ $^ ${LIBS} all: ${ALL} clean: ${RM} core* *.o ${RM} ${ALL}