Setting PHP variables per site w/Uwsgi-plugin-php

I understand this may be a uwsgi question, but I couldn't find any place to ask it other than here.

My setup:
- Debian 7.x Wheezy
- Nginx 1.2.1
- uwsgi, uwsgi-emperor, uwsgi-plugin-php, uwsgi-plugin-python

Problem:
I have some legacy websites that still require 'register_globals' to be enabled. I'd prefer not to enable
it for *all* websites, so I want to set it per site.

In /etc/uwsgi-emperor/vassals/mysite.ini:
[uwsgi]
plugins=php
processes=2
cheaper=1
socket=/var/run/uwsgi/site/%n/php-socket

Is there some way to add an option here to set PHP.INI variables like 'register_globals'?

I am using uwsgi to launch applications from Nginx, from what I've read it's the up-and-coming way to do it, and I host a number of python applications as well so I already have it installed. If this is not correct, please let me know. I'm rebuilding my servers and would like to get it as close to 'right' as possible from the start.

Thanks!