My second good idea to add events with interval :

OnTimerSecond
OnTimerMinute
OnTimerHour

Vault doesn't do timers. not sure what you're even asking for here. you can use the bukkit scehduler for this, or your own thread to schedule a time for something to execute.

It's a idea for add a new function to Vault not for update a already exist method !

There is absolutely no point in putting this in Vault when you can accomplish it on your own via simple Java methods.
http://docs.oracle.com/javase/1.4.2/docs/api/java/util/Timer.html