session_register() Killing MySQL Connection

Hi, Friday night I upgrade my server with the following: Apache 1.3.27 PHP 4.3.0 MySQL 3.23.54a Mod_SSL 2.8.12 OpenSSL 0.9.7 ZendOptimizer 2.1.0 Immediately I started having really weird problems that proved almost impossible to debug. I finally narrowed it down to a few lines of code that get included at the top of all the pages: <?php if(!$REFER_SITE){ $REFER_SITE = $HTTP_REFERER; session_register("REFER_SITE"); } ?> (I already know about the register_globals thing and I'm working on getting rid of it, but that will be a long road)... If both $REFER_SITE and $HTTP_REFERER are uninitialized ($HTTP_REFERER may only be empty) then session_register() kills the database connection on the page and none of my queries work... mysql_error() simply shows "Query was empty". I created an otherwise empty page that had only the code above, a database connection, and a query and confirmed that this is the case. I bring this to the list only to help others avoid the same 3 days of nightmarish hell I've just enjoyed on a large production site with goblins... And to confirm that the above is correct and seek possible long term solutions. Adding this line above session_register() is a temporary solution: if(!$REFER_SITE){ $REFER_SITE = ""; } Thanks all! Brian Allen brian@gzmarketing.com