Apparently Zend made Dmitry an offer he couldn't refuse :)
From chat log of July 2nd, 2003:
<@Zeev> Turck_ is copying every darn thing that we're doing
<@Zeev> I'm really not sure why this Dmitri guy is doing it
<@Derick> Zeev: ever asked him?On internals@php.net yesterday:
From: Dmitry Stogov <dmitry - zend - com>
To: internals@lists.php.net
Subject: [PHP-DEV] CVS Account Request: dmitry
Overall & engine development