Upstream has a policy of only supporting one autoconf version with any given PostgreSQL version; which is good for ensuring repeatable results for PostgreSQL, but it's not very tenable in the Fedora/RHEL world. Dike out the check. diff -Naur postgresql-8.4.2.orig/configure.in postgresql-8.4.2/configure.in --- postgresql-8.4.2.orig/configure.in 2009-09-03 20:36:50.000000000 -0400 +++ postgresql-8.4.2/configure.in 2009-09-04 13:03:07.000000000 -0400 @@ -19,10 +19,6 @@ AC_INIT([PostgreSQL], [8.4.2], [pgsql-bugs@postgresql.org]) -m4_if(m4_defn([m4_PACKAGE_VERSION]), [2.61], [], [m4_fatal([Autoconf version 2.61 is required. -Untested combinations of 'autoconf' and PostgreSQL versions are not -recommended. You can remove the check from 'configure.in' but it is then -your responsibility whether the result works or not.])]) AC_COPYRIGHT([Copyright (c) 1996-2009, PostgreSQL Global Development Group]) AC_CONFIG_SRCDIR([src/backend/access/common/heaptuple.c]) AC_CONFIG_AUX_DIR(config)