you can create other particles when shuriken is at same X position as the particle generator or in near vicinity.
the particle object as lukew said i don't think has individual capabilities, even though i kinda remember something about it being worked on, not sure if was implemented already (i don't use the particle object that often ... very rarely).
but you can create your own custom particle generator using a every 0.05 seconds condition and create a sprite action using the event sheet.