Nikon has released a firmware update for its D40 and D40x DSLRs.
Version 1.12 for the D40 and Version 1.01 for the D40x improve compatibility of
both cameras with Nikon's new EN-EL9a batteries. With the updated firmware, the
D40 should deliver approximately 510 shots in single-frame shooting mode using
the EN-EL9a, according to CIPA standard tests, rather than 470 with the original
EN-EL9 pack.