[root@azuretalon potionstore]# ls /var/lib/pgsql/
backups  data  pgstartup.log
[root@azuretalon potionstore]# POSTGRES_INCLUDE=/var/lib/pgsql/ gem install postgres
Building native extensions.  This could take a while...
ERROR:  Error installing postgres:
	ERROR: Failed to build gem native extension.

/usr/bin/ruby extconf.rb install postgres
extconf.rb:53: warning: Insecure world writable dir /var/www/vhosts/bin, mode 040777
extconf.rb:53: command not found: pg_config --libdir
checking for main() in -lpq... no
*** 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=/usr/bin/ruby
	--with-pgsql-dir
	--without-pgsql-dir
	--with-pgsql-include
	--without-pgsql-include=${pgsql-dir}/include
	--with-pgsql-lib
	--without-pgsql-lib=${pgsql-dir}/lib
	--with-pqlib
	--without-pqlib
Could not find PostgreSQL build environment (libraries & headers): Makefile not created


Gem files will remain installed in /usr/lib/ruby/gems/1.8/gems/postgres-0.7.9.2008.01.28 for inspection.
Results logged to /usr/lib/ruby/gems/1.8/gems/postgres-0.7.9.2008.01.28/ext/gem_make.out
[root@azuretalon potionstore]#