Exim transport config, need variables

I don't normally use exim, and I can't find anything on the variables so what I need is to be able to extract the "from" address from an email. Currently its "$local_part@$domain" but I think there is an issue with it randomly selecting any email account setup on the server and not the one being passed in the email header. Anyone know the correct variables?

Maybe if you tell us exactly what you are trying to do with the data then I could probably help you out, have you considered parssing the info directly from the header using a perl script, which would tie in with exim nicely.

The problem is arising from an integration between a clients emailing script, exim and Amazon SES. When the emailing script sends out newsletters it will use Amazon SES as a transport. To verify with Amazon, it requires a validated address which is in a file. The problem is that the mailing script uses many different email addresses on the server (which the mailing script has no knowledge of) so instead of having 1 email address for newsletters validated, every email account needs to be. This is even more of a problem as it jumps cross-domain. The domain is on x.com and its also using emails from y.com

The integration with SES I'm using is http://www.csrdu.org/nauman/2011/08/12/setting-up-exim-to-use-amazon-simple-email-service-ses/

The code I believe to be the issue is: