It's been my experience that if there's a meaning behind a person's username/handle it's usually a personal one. Given this, wouldn't you agree that if you have a personal question about another user that it best to ask them directly, rather than asking random strangers on a completely different forum?
Most of us here have probably never been to the "Israeli forum" you reference, much less had any meaningful interaction with the user "ca1" to be able to know the meaning of their username. We could speculate until we're all blue in the face, and probably never come even close to the actual reason.