What I would do is keep the raw imported data in one field and create a second field that's an auto-enter calculation to pull out everything between the "<" and ">" of the first field. Then make your relationship between the email address of the contact and this second, parsed email address in the emails table.
Any way you do it, you're correct in assuming you'll need to strip out all but the email address to make the portal work.
Thanks Brian that makes sense to me. The wrinkle that I found was simply some of the to's or cc fields have comma seperated names with the list and I want to get the records matched back up with the particular contact. So my strategy it sounds like is to strip the extra info out into that calculated field and then in other programs I would just simply put each name in a slot in an array and then do the relationship back with the array. So I think I just have to work out the syntax and language FMP uses. I think the same logic will let me show all the from, cc, to entries for the contact in the same portal too.Owen