sync applet turns on on every boot

I don't want to have Ubuntu One sync enabled, so I just click on the menu option to turn it off. The problem is that it turns on again on the next system boot, so I have to switch it off again.

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: indicator-sync 12.10.5daily13.03.28.1-0ubuntu1
ProcVersionSignature: Ubuntu 3.8.0-25.37-generic 3.8.13
Uname: Linux 3.8.0-25-generic x86_64
ApportVersion: 2.9.2-0ubuntu8.1
Architecture: amd64
Date: Wed Jun 19 15:04:39 2013
InstallationDate: Installed on 2011-12-24 (543 days ago)
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111011)
MarkForUpload: True
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=es_ES.UTF-8
 SHELL=/bin/bash
SourcePackage: indicator-sync
UpgradeStatus: Upgraded to raring on 2013-06-16 (2 days ago)