inside the iron is a pressure vessel that stores pressure, turning hot water into steam, it may be that this leaking, a common problem on this type of iron, as the pressure cracks the vessel. your first point of contact should be to tefal informing them of the proble, they had a recall of the irons at some point, whether this has expired i do not know, but they would cetainly have the details of a repair agent in your area.
Will Stirling
May 2009