unable to upgrade with the do-release-upgrade

[Pivert]

The error is:

Could not determine the upgrade

An unresolvable problem occurred while calculating the upgrade.

This can be caused by:
* Upgrading to a pre-release version of Ubuntu
* Running the current pre-release version of Ubuntu
* Unofficial software packages not provided by Ubuntu

If none of this applies, then please report this bug using the
command 'ubuntu-bug ubuntu-release-upgrader-core' in a terminal.

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: ubuntu-release-upgrader-core 1:0.205.7 [origin: unknown]
ProcVersionSignature: Ubuntu 3.11.0-26.45-generic 3.11.10.12
Uname: Linux 3.11.0-26-generic i686
ApportVersion: 2.12.5-0ubuntu2.2
Architecture: i386
CrashDB: ubuntu
Date: Sun Sep 28 16:52:59 2014
InstallationDate: Installed on 2010-10-24 (1434 days ago)
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release i386 (20101007)
MarkForUpload: True
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=en_GB
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_GB.utf8
 SHELL=/bin/bash
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to saucy on 2014-09-28 (0 days ago)