According to E! Online it seems that Battlestar Galactica cast member Jamie Bamber, he played Lee Adama on the show, could surface on Dollhouse Season 2 as a character "heavily involved" in an engagement. Also, Michael Hogan can be seen in the second episode of the season.
In addition to this, Alexis Denisof (Angel) will be guest starring on Dollhouse. Apparently, Summer Glau (Terminator: The Sarah Connor Chronicles) could be making an appearance as well. At present we don't know what parts these characters will play.