[Zope-dev] ZCatalog searching for missing values

Hi all, We've installed Kavio's CatalogQuery product and are very happy with it. Haven't looked at the ZOQLMethod from iuveno yet, but both look like great steps in the right direction. I have one question: is it possible using a normal catalog query or Kavio's catalog query to check if a value is not set? The representation returned is Missing.Value, but I seem to be unable to say, e.g, 'Description == Missing.Value' etc. How hard is it to add such functionality? Bye, -- Bjorn