Good point. Doing some google searches on "lightning in eyewall" and I hit an interesting one:

http://www.usatoday.com/weather/resources/askjack/wahlight.htm

A quote in it from Peter Black who apparently used to (and may still) fly into hurricanes: "There was lightning reported in Camille's eyewall by the last Air Force recon crew that flew into it before landfall...."

Another discussion about lightning, including in eyewalls:
http://www.weatherwise.org/qr/qry.hurlit.html