Either that, or the guy really was as old as the hills. It had long been established that Colonial life spans seem to be much longer than ours. Adama himself alluded to this in "Lost Planet of the Gods" when he was talking about being a hundred or couple hundred yahrens younger and going after someone like Serena. IIRC, the original SoaSW script gave mention to the battlestars which were hundreds (over 500) of yahrens old, constantly being patched over and rebuilt to maintain a press in the war effort. It's entirely possible that this person is 1000+. Remember, as a show heavily rooted in Biblical ties, there were strong references in Genesis to the descendants of Adam & Eve, their names and extremely long lifespans, being in direct correlation to their piety. The more holy you were, the longer you were allowed to live by God. That directly implies that Adama, by his stature in the Council and a direct line descendant of the Lords of Kobol and a religious leader, would be of a certain advanced age. The other guy may very well be even more pious than Adama, then. Which begs the question, why was he reminiscing about philandering with multiple women in his youth and bragging to Starbuck about it, at the same time congratulating him on his "efforts"? I guess perhaps God also has a sense of humor...
