Historical version. PostgreSQL 9.0 has reached end of support. 2015-10-08. See the current manual.
E.221. Release 6.4.2
Release Date: 1998-12-20
The 6.4.1 release was improperly packaged. This also has one additional bug fix.
E.221.1. Migration to Version 6.4.2
A dump/restore is not required for those running 6.4.*.
E.221.2. Changes
Fix for datetime constant problem on some platforms(Thomas)
Report a documentation issue
Read the upstream documentation. For corrections, first check the current manual.