People, I found the answer here: http://wiki.rubyonrails.org/rails/pages/PostgreSQL I fixed it with 1 (one!) command line: gem install postgres -- --with-pgsql-include-dir=/usr/local/pgsql/include --with-pgsql-lib-dir=/usr/local/pgsql/lib More info: $ $ $ gem install postgres -- --with-pgsql-include-dir=/usr/local/pgsql/include --with-pgsql-lib-dir=/usr/local/pgsql/lib Bulk updating Gem source index for: http://gems.rubyforge.org Building native extensions. This could take a while... Successfully installed postgres-0.7.1 $ $ $ $ $ $ gem list|grp post gem list|grp post postgres (0.7.1) The extension library to access a PostgreSQL database from Ruby. postgres-pr (0.4.0) A pure Ruby interface to the PostgreSQL (>= 7.4) database $ rake db:migrate (in /pt/webprops/edgar411/e10) ERROR: relation "schema_info" already exists STATEMENT: CREATE TABLE schema_info (version integer) == AddSessions: migrating ===================================================== -- create_table(:sessions) NOTICE: CREATE TABLE will create implicit sequence "sessions_id_seq" for serial column "sessions.id" NOTICE: CREATE TABLE will create implicit sequence "sessions_id_seq" for serial column "sessions.id" NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "sessions_pkey" for table "sessions" NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "sessions_pkey" for table "sessions" -> 0.2986s -- add_index(:sessions, :session_id) -> 0.0086s -- add_index(:sessions, :updated_at) -> 0.0091s == AddSessions: migrated (0.3176s) ============================================ $ $ $