[Plugin: Google Analytics for WordPress] Secondary Adsense Domains

I am tracking primary domain without any problems. However, to track a secondary domain Google Analytics is saying that I need to include another code snippet at the top of every page.
This plugin has a place for the main Analytics code but I don’t see anywhere to include this extra code snippet. Is there a way to easily include the extra code?
Thanks

http://wordpress.org/extend/plugins/google-analytics-for-wordpress/