Hi Bernhard, are you proposing of writing some rrd version handling support layer :-) ? especially with the planed machine indendent data format, this could come in handy ! cheers tobi -- Tobi Oetiker, OETIKER+PARTNER AG, Aarweg 15 CH-4600 Olten http://it.oetiker.ch tobi at oetiker.ch ++41 62 213 9902