Is the Euro about to break up?

Watching the Greece and the larger Euro zone crisis unfold, it seems to me that it is no longer inconceivable to think of a break up of the Euro! The huge pressure of disparate fiscal policies resulting in each members' economy becoming increasingly out of tune with the centralized monetary policy (ECB) will require such a move. Put simply, one of Greece's hindrance in being able to address its current problems is its inability to devalue its currency! Therefore, the first exit candidate would naturally be Greece!
Under these circumstances I have been wondering whether the ECB / Euro nations even have a Disaster Recovery Plan to revert to their erstwhile national currencies. i.e., have they documented the procedures will kick in once they decide to break away and have they stored enough drachmas, francs, marks etc in their vaults to issue the same quickly?