/opt/local/bin/ruby extconf.rb install postgres
checking for main() in -lpq... yes
checking for libpq-fe.h... yes
checking for libpq/libpq-fs.h... yes
checking for PQsetClientEncoding()... no
checking for pg_encoding_to_char()... yes
checking for PQfreemem()... no
checking for PQserverVersion()... no
checking for PQescapeString()... no
creating Makefile

make
/usr/bin/gcc-4.0 -I. -I. -I/opt/local/lib/ruby/1.8/i686-darwin9.2.0 -I. -DHAVE_LIBPQ_FE_H -DHAVE_LIBPQ_LIBPQ_FS_H -DHAVE_PG_ENCODING_TO_CHAR -I/opt/local/include -fno-common -O2  -fno-common -pipe -fno-common  -c libpq-compat.c
libpq-compat.c: In function ‘PQescapeBytea’:
libpq-compat.c:104: warning: incompatible implicit declaration of built-in function ‘sprintf’
libpq-compat.c:104: warning: pointer targets in passing argument 1 of ‘sprintf’ differ in signedness
libpq-compat.c: In function ‘PQunescapeBytea’:
libpq-compat.c:158: warning: incompatible implicit declaration of built-in function ‘strlen’
libpq-compat.c:158: warning: pointer targets in passing argument 1 of ‘strlen’ differ in signedness
/usr/bin/gcc-4.0 -I. -I. -I/opt/local/lib/ruby/1.8/i686-darwin9.2.0 -I. -DHAVE_LIBPQ_FE_H -DHAVE_LIBPQ_LIBPQ_FS_H -DHAVE_PG_ENCODING_TO_CHAR -I/opt/local/include -fno-common -O2  -fno-common -pipe -fno-common  -c postgres.c
postgres.c:41: error: static declaration of ‘PQserverVersion’ follows non-static declaration
/opt/local/include/libpq-fe.h:262: error: previous declaration of ‘PQserverVersion’ was here
postgres.c: In function ‘Init_postgres’:
postgres.c:2676: error: ‘pgconn_protocol_version’ undeclared (first use in this function)
postgres.c:2676: error: (Each undeclared identifier is reported only once
postgres.c:2676: error: for each function it appears in.)
postgres.c:2677: error: ‘pgconn_server_version’ undeclared (first use in this function)
make: *** [postgres.o] Error 1