Hi, I just upgraded pjproject to revision 2961 and got the following error message when building (on Linux): ... gcc -c -Wall -DPJ_AUTOCONF=1 -pipe -DNDEBUG -DPJ_DEBUG=0 -O2 -I../include \ -o output/pjlib-i686-pc-linux-gnu/sock_bsd.o \ ../src/pj/sock_bsd.c ../src/pj/sock_bsd.c:134: error: ?TCP_NODELAY? undeclared here (not in a function) make[3]: *** [output/pjlib-i686-pc-linux-gnu/sock_bsd.o] Error 1 ... I guess that somewhere in the chain of include files "#include <netinet/tcp.h>" is missing. Best regards, Dan