Macintosh:~ sphericuser$ sudo gem install postgres
Password:
Building native extensions.  This could take a while...
ERROR:  Error installing postgres:
	ERROR: Failed to build gem native extension.

/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby extconf.rb install postgres

		===========   WARNING   ===========

		You are building this extension on OS X without setting the
		ARCHFLAGS environment variable, and PostgreSQL does not appear
		to have been built as a universal binary. If you are seeing this
		message, that means that the build will probably fail.

		Try setting the environment variable ARCHFLAGS
		to '-arch i386' before building.

		For example:
		(in bash) $ export ARCHFLAGS='-arch i386'
		(in tcsh) $ setenv ARCHFLAGS '-arch i386'

		Then try building again.

		===================================
		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()... no
checking for PQfreemem()... no
checking for PQserverVersion()... no
checking for PQescapeString()... no
creating Makefile

make
gcc -I. -I. -I/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/universal-darwin9.0 -I. -DHAVE_LIBPQ_FE_H -DHAVE_LIBPQ_LIBPQ_FS_H -I/opt/local/include/postgresql82  -fno-common -arch ppc -arch i386 -Os -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: 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
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
gcc -I. -I. -I/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/universal-darwin9.0 -I. -DHAVE_LIBPQ_FE_H -DHAVE_LIBPQ_LIBPQ_FS_H -I/opt/local/include/postgresql82  -fno-common -arch ppc -arch i386 -Os -pipe -fno-common  -c postgres.c
postgres.c:41: error: static declaration of ‘PQserverVersion’ follows non-static declaration
/opt/local/include/postgresql82/libpq-fe.h:262: error: previous declaration of ‘PQserverVersion’ was here
postgres.c:41: error: static declaration of ‘PQserverVersion’ follows non-static declaration
/opt/local/include/postgresql82/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)
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)
lipo: can't open input file: /var/tmp//ccSBpe9q.out (No such file or directory)
make: *** [postgres.o] Error 1


Gem files will remain installed in /Library/Ruby/Gems/1.8/gems/postgres-0.7.9.2008.01.28 for inspection.
Results logged to /Library/Ruby/Gems/1.8/gems/postgres-0.7.9.2008.01.28/ext/gem_make.out