I am working with timezones in a Java application using JodaTime. I encounter a problem when trying to build a DateTimeZone (JodaTime) object from the id of a java timezone.
I'll add this as a new post, as it provides the answers to my question. SystemV timezones were used in an old UNIX OS, that was named, you guessed it, UNIX SYSTEM V. After discussing with my team, we decided that they are of no importance to non-programers and even to programmers nowadays. So we decided not to use them in our application.
Some references about the SystemV timezones: