Thanks to DarkUFO reader Marilyn for the following from IMDB.
In my ongoing research to find out if HIC will be returning to Lost for S6, I found this on imdb.com recently. Not only is he listed to be on Episode 6 of Season 6 of Lost, but if you click on "Lost" there's a link for Season 6, and the same list of actors is there as well. Also note the addition of Emilie DeRavin back to the main cast and the deletion of Elizabeth Mitchell. You know more about imdb.com than I do, I don't post or edit on imdb, thought i'd send it to your rumour mill. It does say to his credits he's active on Lost 2005-2010.
Source: IMDB