If you carry a kubaton [ one designed as a kubaton and sold as such ] Mac is correct.
The "Stick of Death" as my small wooden stick has affectionately become known since the unarmed self defense class in Fla a few months back is not a kubaton, it's a small piece of wooden dowel.
It's not made as a kubaton or any other weapon. It's a small wooden stick. You could as easily use or carry one of a pair of chopsticks and do the same thing. Chopsticks are not illegal to board on the plane, and until they restrict pieces of wood on the plane, my little wooden stick is not against the law.
In your pocket, it's not going to set the detectors off, and can be expainned away as an acupressure tool needed due to being seated for long periods of time. Id like to see someone explain how a small wooden dowel in your pocket is against the law.
It's not a weapon until it's used as a weapon. A pen does the same thing the kubaton does, so in essense, they'd ban pens and pencils on planes as they could be used as a kubaton.
Stay away from commercial products that are sold as kubatons and I don't see the problem. You just have to be able to articulate what you intend to use it for, and that's ONLY if it's found [ which it won't be as it's wood and not going to set off the bells and whistles for you to be searched ].