gnomebase.bbclass is looking for tar.bz2 tarballs on the Gnome ftp servers; Gnome no longer uses bz2 archives, the tarballs for recent releases are only available in the .tar.xz format.
Currently many of the package that are currently in use, have not been repackaged with .xz tarballs, so it's hard, we need to create a fallback for both bz2 and xz
I think also it is unlikely that any packages that were released already will be repackaged. I think there was a transition period during which both bz2 and xz were being relased, but the recent packages are xz-only. To be fair, you only run into this if you try to update a package to a newer version than is currently in poky.
Agreed, this does need to be address for the newer gnome archives.
Best way to handle this would be to add a ${<pick a name>} to the replace the .bz2 part of the source URI and set a default =? ".bz2" in the gnomebase.bbclass, then as new packages using .xz format created, change the ${<pick a name>} in the packages's recipe file to be ".xz". Can you please provide an appropriate patch? Thanks
http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=99822cd4a01342565f803678baba49d74192b7d1