Since 4.0.3, PHP reports the error given in the bug description. I checked the returned value before:

----------------------------------------------------

  $conn = pg_connect("dbname=" . VEDB_DBNAME);
  if (!$conn)
    {
      fatal_error("Could not connect to database", __FILE__, __LINE__);
    }
	
  $query = "select $field from $table where $field = '$_value'";
	
  $res = pg_exec($conn, $query);

----------------------------------------------------

I can't really understand why that error occurs in the last line (pg_exec).

configure line:
./configure' '--with-apxs=/usr/lib/apache/bin/apxs' '--without-mysql' '--with-config-file-path=/etc/php4' '--sysconfdir=/etc/php4' '--with-pgsql=/usr/lib/pgsql' '--with-gnu-ld' '--enable-magic-quotes' '--enable-bcmath' '--enable-calendar' '--with-gdbm' '--with-db3' '--with-gd=/usr' '--with-ttf' '--with-gettext' '--with-readline' '--with-sysvsem' '--with-sysvshm' '--enable-versioning'

I use PostgreSQL 7.0.2.

The very same script runs flawlessly with PHP 4.0.2.