This seems to be some sort of ABI breakage between the two versions. On edgy re-building/re-installing apt (both amd64/i386) fixes the issue.
-- synaptic no longer builds after g++-4.1 (4.1.1-13ubuntu2) to 4.1.1-13ubuntu3 upgradae https://launchpad.net/bugs/62461 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
