I had a little incident with lighters before. I used to travel with a Xikar Executive since it's cheap. I usually pack it in a checked luggage. I had no problem with it for a while until it went missing. I assumed that it was confiscated by security since it wasn't allowed (I think).
I started travelling around with a Xikar EXII, thinking that it's a softer flame and was allowed. I usually have it on me and go thru security checkpoint with it. I had no problem going through security, for a while at least. One time in SFO, it caugh the eyes of a TSA agent and decided to check with his supervisor. She took a look at the flame and said that it wasn't allowed. I argued for a while and we even checked with a explosive expert who also agreed with her. I was offered to surrender it or try to send it back through a travel agent or post office. I attempted to do so, but no one would ship it. I decided to try my luck and go through another security area. No one even cared this time....
Til this day, I am still not 100% sure about the rules on lighters, but I no longer travel with a lighter!