I'm pretty sure within the last year someone on here had a thread goin about just this. he took several cuttings, placed them in a few diff arrangments designed to keep them for a period of time. cheking on them, spraying them with water, keeping them in the fridge. Then testing if the would root at a later time.. starting with a week, running to 6 months of storage (i think, i could be wrong on the duration).
either way, i remember it didnt go well for him, and the experiment was abandoned i believe.