pg-0.10.0 fails to compile on OS X Snow Leopard about ruby-pg HOT 4 CLOSED

ld: warning: in /Developer/SDKs/MacOSX10.6.sdk/usr/local/lib/libpq.dylib, 
	file was built for i386 which is not the architecture being linked (x86_64)
Undefined symbols:
  "_PQconnectdb", referenced from:
      _t in ccxwIhEo.o

$ rvm 1.9.2 ruby -v
ruby 1.9.2p0 (2010-08-18 revision 29036) [x86_64-darwin10.4.0]

  rvm 1.9.2-head gem install pg -- \
    --with-pg-config=/usr/local/pgsql-9.0/bin/pg_config

$ which pg_config
/usr/local/pgsql/bin/pg_config
$ ls -l /usr/local/pgsql
lrwxr-xr-x  1 cypher  wheel     9B Dec  7 16:41 /usr/local/pgsql@ -> pgsql-9.0
$ pg_config
BINDIR = /usr/local/pgsql-9.0/bin
DOCDIR = /usr/local/pgsql-9.0/share/doc
INCLUDEDIR = /usr/local/pgsql-9.0/include
PKGINCLUDEDIR = /usr/local/pgsql-9.0/include
INCLUDEDIR-SERVER = /usr/local/pgsql-9.0/include/server
LIBDIR = /usr/local/pgsql-9.0/lib
PKGLIBDIR = /usr/local/pgsql-9.0/lib
LOCALEDIR = 
MANDIR = /usr/local/pgsql-9.0/man
SHAREDIR = /usr/local/pgsql-9.0/share
SYSCONFDIR = /usr/local/pgsql-9.0/etc
PGXS = /usr/local/pgsql-9.0/lib/pgxs/src/makefiles/pgxs.mk
CONFIGURE = '--with-openssl' '--with-pam' '--with-krb5' '--with-gssapi' '--with-ldap' '--enable-thread-safety' '--with-bonjour' '--with-python' '--without-perl' '--enable-nls' '--with-libxml' 'CFLAGS=-Os -arch i386 -arch x86_64 -D_FILE_OFFSET_BITS=64' 'LD=gcc -arch i386 -arch x86_64 -nostdlib'
CC = gcc
CPPFLAGS = -I/usr/include/libxml2
CFLAGS = -Os -arch i386 -arch x86_64 -D_FILE_OFFSET_BITS=64 -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement -Wendif-labels -fno-strict-aliasing -fwrapv
CFLAGS_SL = 
LDFLAGS = -arch i386 -arch x86_64
LDFLAGS_SL = 
LIBS = -lintl -liconv -lxml2 -lpam -lssl -lcrypto -lgssapi_krb5 -lldap -lreadline -lz
VERSION = PostgreSQL 9.0.1