I don't think it's fair? That jerk shouldn't have given you a ticket. I would take this one to court. You know he was just screwing with you by giving you a ticket for something else because he knew that if he gave you a ticket for not having a log book it would have never fly in court. The judge would have thrown it out and reprimanded the DOT officer for doing such a stupid thing!
Dude throw out the DOT rule book! No one uses it anymore, it's over rated. If any one screws with you just tell them that you pay their wages and they should have gone to college and them tell them to get a real job. Don't sweat the DOT, they are just there to make Joe Public think the state really cares about safety. Log books??? Seriously, Who really needs them?