[SBS 2011] Exchange Safelist Aggregation

I configured Exchange with a couple of blacklist-services like SORBS and Spamhaus. Then we had some customers complaining about e-mail returned by the Exchange spamfilter. I manually added their domains to the Exchange Whitelist, using the Management Shell. Problem solved.

But... I did some more digging. Outlook 2003 (and upwards) create a list of Safe Senders. After reading several articles (http://technet.microsoft.com/en-us/library/bb125168(v=exchg.141).aspx), I understand Exchange 2010 automatically checks those lists and adds them to AD. Used ADSI edit to check if this works (http://www.msexchange.org/articles-tutorials/exchange-server-2007/security-message-hygiene/using-safelist-aggregation-part2.html) and it does.

What I don't understand is why the previously mentioned customers got their e-mail returned, since they are on the Outlook Safe List. So on the SBS server, I the command "Test-EdgeSynchronization -VerifyRecipient kate@contoso.com" to verify if things work as they should (http://technet.microsoft.com/en-us/library/bb266939.aspx). This results in a faillure: 

SyncStatus                  : NoSyncConfigured
UtcNow                      : 12-06-2013 15:12:47
Name                        :
LeaseHolder                 :
LeaseType                   : None
FailureDetail               : There are no Edge subscriptions for current site "<sitename>"

So how do I get this working?

Simon