Sorry, this is something that you'd need to seek developer assistance with. Current versions of s2Member do not make this possible. That being said, s2Member DOES include quite of bit of detail in the email subscription requests that it sends to AWeber. A good developer that is familiar with AWeber Custom Email Parsers should be able to satisfy your requirements.
Another option would be to use MailChimp instead. s2Member's integration with MailChimp is better than it is with AWeber. s2Member can be configured quite easily to use MailChimp Interest Groups, and with a bit of tweaking, can also pass through Custom Registration Field data through MERGE fields configured inside MailChimp. If you go the MailChimp route, please see this post for an example of adding custom MERGE fields with s2Member hacks.
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