Calendar keeps highlighting the day when the system was booted rather than the current date

[Teo]

Steps to reproduce:
- boot
- wait at least one day
- click on the clock to display the datetime widget

Expected: the date shown in text and the day highlighted in the calendar widget should be consistent and both should correspond to the current date

Observed: the date shown as text on the top is correct (current date), but the one highlighted on the calendar remains the one when the system was booted!!

See screenshot

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: indicator-datetime 13.10.0+13.10.20131023.2-0ubuntu1.1
ProcVersionSignature: Ubuntu 3.11.0-20.35-generic 3.11.10.6
Uname: Linux 3.11.0-20-generic x86_64
ApportVersion: 2.12.5-0ubuntu2.2
Architecture: amd64
Date: Sat May 24 17:00:41 2014
InstallationDate: Installed on 2013-10-11 (224 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
MarkForUpload: True
SourcePackage: indicator-datetime
UpgradeStatus: Upgraded to saucy on 2014-02-23 (90 days ago)

[Teo (teo1978)]

This and #1322867 are probably somehow related