I am using tar-1.13.18 built from the source code. Some of the other packages that I attempted to build from source failed because they were packed using bzip2 instead of gzip, and the 'tar xIfp' command in rules.unpack failed to unpack them.
Examining the source for tar revealed that the bzip2 option for tar is not -I anymore, it is -j. How long has this been the case? And what to do about all those broken scripts?