I have managed to transfer the upgrade logs and they are attached here for investigation.
** Attachment added: "Dist-Upgrade Log" http://librarian.launchpad.net/4159902/dist-upgrade.log -- upgrade failed for postfix, mailx and mantis https://launchpad.net/bugs/59268 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
