where is ISubscriber on TFS 2013?

I made a side plugin for TFS 2012 , that implements ISubscriber (from namespace Microsoft.TeamFoundation.Framework.Server file  Microsoft.TeamFoundation.Framework.Server.dll ) . Now  upgraded to TFS 2013 and the dll Microsoft.TeamFoundation.Framework.Server.dll  is missing .

I tried http://social.msdn.microsoft.com/Forums/vstudio/en-US/25fde204-12ba-4e0d-be5d-4d561c588c47/isubscriber-plugins-not-working-in-tfs-2013-preview?forum=tfsgeneral inserting reference to Microsoft.VisualStudio.Services.Common.dll

where is the ISubscriber in TFS 2013? in which namespae and which dll?