PHP4 will be removed from servers on December 30, 2009 beginning at 1 AM EST (-0400 GMT).  PHP5.3, compiled with mysqlnd, will replace legacy PHP4 servers accessible on port 9000.  Clients that rely on PHP4 have been individually contacted, while all others will remain unaffected by this transition.

Following installation of PHP 5.3, PostgreSQL will be upgraded from 8.2 to 8.4.  During this leg of the upgrade database access will be briefly taken offline to update database definitions.  E-mail delivery will be interrupted momentarily for 1 – 3 minutes while the database is offline.  E-mail sent during the window will be redelivered within a hour.

Note: this plan has changed from the original, which suggested upgrading the primary server, after a client expressed concern over Drupal PHP 5.3 incompatibility.  Replacing PHP4, which was discontinued by its developers on December 31, 2007, will affect significantly fewer clients than replacing 5.2, which is the latest version supported by some applications that many clients utilize.

PHP 4 Removal, PHP 5.3 Addition, PostgreSQL Upgrade