I mean, i once read an article by Ajahn Brahm called "Travellogue to the jhanas" and there he said that when one is in a jhana, one isn't aware of one's surroundings. That should make it impossible to have jhana while walking, no?
Edit: here is the source
Again, because the quality of knowing is very strong but very narrow in these states, while you are in these states, there is no way that you can truly assess where you are and what's happening to you. The ability to know through thinking, through analysing, is taken away from you in these states. You usually have to wait until you emerge from these states, until your ordinary thinking returns again, so you can really look back upon and analyse what has happened.
http://www.dharmaweb.org/index.php/Trav ... rahmavamso