Although there has always been some suspicion regarding the inscription, perhaps this is what Biblical Archaeology Review was referring to a few months ago when it quoted an expert as saying, "The inscription 'is now clearly assessed to be a forgery,'" without any further elaboration.
The same expert also said at the time that up to a third of the 'inscribed materials' in the Israel Museum were possibly fake. If you wonder how that is possible, you need only read the story of how the Israel Museum secured the pomegranate for its collection:
[T]he Israel Museum was approached about buying [the pomegranate] in 1987. It decided to do so after well-known archaeologist Nahman Avigad vouched for the pomegranate's authenticity - following a cursory examination that apparently relied mainly on a magnifying glass. The purchase itself was concluded in a highly secretive manner. The museum did not know the owner's identity; all negotiations were conducted via intermediaries. And the museum was asked to deposit the money in a numbered Swiss bank account, after which it was directed to a safe containing the pomegranate.Hmmm. Not suspicious at all!