The previous version is no longer available:
$ wget ftp://ftp.free.fr/mirrors/ftp.debian.org/pool/main/c/ca-certificates/ca-certificates_20150426.tar.xz
--2016-01-03 22:03:48-- ftp://ftp.free.fr/mirrors/ftp.debian.org/pool/main/c/ca-certificates/ca-certificates_20150426.tar.xz
=> 'ca-certificates_20150426.tar.xz'
Resolving ftp.free.fr (ftp.free.fr)... 212.27.60.27, 2a01:e0c:1:1598::1
Connecting to ftp.free.fr (ftp.free.fr)|212.27.60.27|:21... connected.
Logging in as anonymous ... Logged in!
==> SYST ... done. ==> PWD ... done.
==> TYPE I ... done. ==> CWD (1) /mirrors/ftp.debian.org/pool/main/c/ca-certificates ... done.
==> SIZE ca-certificates_20150426.tar.xz ... done.
==> PASV ... done. ==> RETR ca-certificates_20150426.tar.xz ...
No such file 'ca-certificates_20150426.tar.xz'./cc @kazuhiko, @vpelletier, @romain