There's been quite a few changes recently.
Currently using 2012e-0ubuntu0.12.04.1, but in precise-updates there is 2013d-0ubuntu0.12.04
http://packages.ubuntu.com/precise-updates/tzdata
http://mirrors.us.kernel.org/ubuntu//pool/main/t/tzdata/tzdata_2013d-0ubuntu0.12.04_all.deb
Version: wmf-deployment
Severity: enhancement