When migrating to Confluence 4.0, we are experiencing issues with Activity Streams not displaying issues from spaces correctly. We have tested other methods (user specific filtering, update date) and they are correctly displaying activity, however when we try to apply the global filter of certain spaces, we only see information from when the space was created (sometimes as much as a year ago, with no activity since then, when there has definitely been activity), nothing current.
I'm not sure if this is relevant, but several of the spaces have several (3-8) components to which all issues are tied. This had no negative effect on issue reporting in the Activity Stream before migrating, so I doubt it would be the cause.