First of all allowing register_globals on, on a server is real stupid, it is a security risk that no hosting company should accept, but sometimes for old scripts it is necessary to have it on, in this case should be enabled on the customer account on the .htaccess file or if the server is running with SuExec support then on the php.ini file.
Usually entering the line:
to the php.ini on the public_html should work, but on some servers we have noticed that this is not working. Unfortunately we do not know the exact reason for this issue, but we have another method to enable this.
First create a file called php5.cgi with 755 permissions and add the following in it.
exec /usr/local/cpanel/cgi-sys/php5 -c /home/account-username/public_html/php.ini
(change the user names, and copy the php.ini file in to the public_html)
Then add the following lines in the .htaccess file.
Options All -Indexes
AddHandler application/x-httpd-php5 .php
Action application/x-httpd-php5 /php5.cgi