Problem with logout from Office 365

[Peter Schober]

* eduardo.junior <eduardo.junior+shibboleth at dedalusprime.com.br> [2015-01-08 18:24]:
> You have signed out of these sites:
> 
> BOX-PROD-EDGE (501392)
> Outlook Live (260563)
> 
> We couldn't sign you out of these sites:
> 
> Dedalus Prime (DEDALUSPRIME.COM.BR) 
> 
> --- END OF ERROR MESSAGE ---

That's not coming from a Shibboleth IDP (and the Shib IDP does not
support SLO), so I'm doubtful Shibboleth has anything to do with this.
-peter