pg gem install error - lion osx, bundler, and rvm - ruby-on-rails

Question

I have spent way too many hours trying to fix this.
I reformatted my computer - clean snow leopard, than immediate upgrade to lion.
Xcode 4.2.1 installed
RVM installed
As I setup my environment I finally got to bundle install, and it failed trying to create the PG gem.
I had installed postgresql using macports (wasn't aware its preinstalled in lion). Following instructions here:http://benscheirman.com/2010/06/installing-postgresql-for-rails-on-mac-os-x And ran into more errors trying to install the pg gem:
Installing pg (0.12.0) with native extensions
Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.
/Users/me/.rvm/rubies/ruby-1.8.7-p357/bin/ruby extconf.rb
checking for pg_config... yes
Using config values from /usr/local/bin/pg_config
checking for libpq-fe.h... no
Can't find the 'libpq-fe.h header
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers. Check the mkmf.log file for more
details. You may need configuration options.
Provided configuration options:
--with-opt-dir
--without-opt-dir
--with-opt-include
--without-opt-include=${opt-dir}/include
--with-opt-lib
--without-opt-lib=${opt-dir}/lib
--with-make-prog
--without-make-prog
--srcdir=.
--curdir
--ruby=/Users/sling31/.rvm/rubies/ruby-1.8.7-p357/bin/ruby
--with-pg
--without-pg
--with-pg-dir
--without-pg-dir
--with-pg-include
--without-pg-include=${pg-dir}/include
--with-pg-lib
--without-pg-lib=${pg-dir}/lib
--with-pg-config
--without-pg-config
--with-pg_config
--without-pg_config
Gem files will remain installed in /Users/me/.rvm/gems/ruby-1.8.7-p357/gems/pg-0.12.0 for inspection.
Results logged to /Users/me/.rvm/gems/ruby-1.8.7-p357/gems/pg-0.12.0/ext/gem_make.out
An error occured while installing pg (0.12.0), and Bundler cannot continue.
Make sure that `gem install pg -v '0.12.0'` succeeds before bundling.
I've searched stackoverflow nonstop, and pretty much tried everything.
I removed the macports version, and then decided to try installing with homebrew:
"brew install postgresql"
pg_config gives me:
BINDIR = /usr/local/Cellar/postgresql/9.1.2/bin
DOCDIR = /usr/local/Cellar/postgresql/9.1.2/share/doc/postgresql
HTMLDIR = /usr/local/Cellar/postgresql/9.1.2/share/doc/postgresql
INCLUDEDIR = /usr/local/Cellar/postgresql/9.1.2/include
PKGINCLUDEDIR = /usr/local/Cellar/postgresql/9.1.2/include
INCLUDEDIR-SERVER = /usr/local/Cellar/postgresql/9.1.2/include/server
LIBDIR = /usr/local/Cellar/postgresql/9.1.2/lib
PKGLIBDIR = /usr/local/Cellar/postgresql/9.1.2/lib
LOCALEDIR = /usr/local/Cellar/postgresql/9.1.2/share/locale
MANDIR = /usr/local/Cellar/postgresql/9.1.2/share/man
SHAREDIR = /usr/local/Cellar/postgresql/9.1.2/share/postgresql
SYSCONFDIR = /usr/local/Cellar/postgresql/9.1.2/etc
PGXS = /usr/local/Cellar/postgresql/9.1.2/lib/pgxs/src/makefiles/pgxs.mk
CONFIGURE = '--disable-debug' '--prefix=/usr/local/Cellar/postgresql/9.1.2' '--enable-thread-safety' '--with-bonjour' '--with-gssapi' '--with-krb5' '--with-openssl' '--with-libxml' '--with-libxslt' '--with-python' '--with-perl' '--with-ossp-uuid' '--datadir=/usr/local/Cellar/postgresql/9.1.2/share/postgresql' '--docdir=/usr/local/Cellar/postgresql/9.1.2/share/doc/postgresql' 'ARCHFLAGS='''-arch x86_64'''' 'CC=/usr/bin/llvm-gcc' 'CFLAGS=-O3 -w -pipe -march=core2 -msse4.1 -I/opt/local/include/ossp' 'LDFLAGS=-L/usr/local/Cellar/readline/6.2.2/lib -L/opt/local/lib' 'LIBS=-luuid' 'CPPFLAGS=-I/usr/local/Cellar/readline/6.2.2/include -I/usr/include/libxml2'
CC = /usr/bin/llvm-gcc
CPPFLAGS = -I/usr/local/Cellar/readline/6.2.2/include -I/usr/include/libxml2 -I/opt/local/include/libxml2
CFLAGS = -O3 -w -pipe -march=core2 -msse4.1 -I/opt/local/include/ossp -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement -Wendif-labels -Wformat-security -fno-strict-aliasing -fwrapv
CFLAGS_SL =
LDFLAGS = -L/usr/local/Cellar/readline/6.2.2/lib -L/opt/local/lib -L/opt/local/lib -Wl,-dead_strip_dylibs
LDFLAGS_EX =
LDFLAGS_SL =
LIBS = -lpgport -lxslt -lxml2 -lssl -lcrypto -lgssapi_krb5 -lz -lreadline -lm -luuid
VERSION = PostgreSQL 9.1.2
I tried all of the export rvm_archflags="-arch x86_64" type solutions, but none seemed to make any difference.
Any ideas where I should begin?

Answer 1

I'm not familiar with Brew, but it looks like the pg_config you're invoking is not the one used to configure pg.
So, please try include /usr/local/Cellar/postgresql/9.1.2/bin (expect to have pg_config there) to the path and retry.
Actually, the output says "Using config values from /usr/local/bin/pg_config"
it should be the pg_config in the Brew's path. I guess it's in /usr/local/Cellar/postgresql/9.1.2/bin .

Answer 2

This might help: https://plus.google.com/104769575749979987265/posts/CVdrNMZYU9R
It does for Linux anyways.