OSX 10.9 Mavericks has just been released, Mavericks doesn’t seem to come with Java 6 installed only Java 7 but because of significant changes between Java 6 (developed by Apple) and Java 7 (developed by Oracle) on OSX the current version of Jaikoz only works with Java 6.
Mavericks is meant to inform you to install Java 6 if you try and run a Java 6 application and it doesnt start but on my machine it just silently failed so if Jaikoz is not starting this is probably the problem, or the problem maybe you are using Jaikoz 5.7.0 with iTunes integration.
I am currently working on a Java 7 version of Jaikoz and solving the iTunes problem, should be a new release available by the end of next week.