Or three: Kerry knew this and had his campaign leak this to the press right before the 9/11 commission releases its report and the DNC convention. That way it is in the news for a few days, then these events suck all the oxygen out of the news cycle. When it comes back into the news when Berger gets charged, the Dems can say that it has been thoroughly vetted and the charges are political.
Addendum: And the DNC can get mileage out of saying the Bush Admin 'leaked' this for political reasons. The LSM is compliant, so they will get away with it for a while.