-AC_CHECK_PROG(psql_support, pg_config, yes, no)
-if test x"$psql_support" = x"yes" ; then
+AC_ARG_VAR([PG_CONFIG], [Full pathname of the pg_config program shipped with Postgresql])
+AC_PATH_PROG([PG_CONFIG], [pg_config], [], [$PATH:/usr/local/pgsql/bin:/usr/pgsql/bin])
+if test -n "$PG_CONFIG" ; then
+ AC_SUBST(PG_CONFIG)