Looking at the duplicates of this bug the latest version affected seems to be apt-xapian-index 0.41ubuntu6 from Ubuntu 11.04. While I can't find a specific changelog entry indicating what fixed this it certainly seems fixed in Oneiric and Precise, subsequently I am setting this to Fix Released and will remove the bug pattern for it.
Looking at the duplicates of this bug the latest version affected seems to be apt-xapian-index 0.41ubuntu6 from Ubuntu 11.04. While I can't find a specific changelog entry indicating what fixed this it certainly seems fixed in Oneiric and Precise, subsequently I am setting this to Fix Released and will remove the bug pattern for it.