Podemos añadir también la primera gran pifia: En el 2010, el incidente conocido como el
value overflow incident hizo que en Agosto del 2010, en el bloque 74.638, la suma de dos outputs generasen un overflow negativo, que dio paso a una TX con 92.233.720.368,54277039 BTCs …
Se tardó algunas (muy pocas) horas en resolver...
It looks like we overtook the bad chain somewhere around 74689. 0.3.9 and lower nodes have been responding with the current block number for some hours now.
That means it's no longer necessary to delete blk*.dat before upgrading. You can just upgrade and it'll reorg away the bad block chain.
Thanks to everyone for the quick response!