Unfortunately, this change was not included in 6.5. I've put it in the plan for the next release.
Meanwhile, I'd like to comment it a little bit.
The Items collection stores events loaded from the DataSource during data binding. It's ok to check it after it's loaded (after calling DataBind(), that includes BeforeEventRender and BeforeCellRender events).
Up to 6.2 release, the loaded events were stored in the ViewState and available during PostBacks and CallBacks even before DataBind() was called. In 6.2, a new property was added to control this behavior (StoreEventsInViewState). The default value is false.
I'm not sure if it's your case but I would strongly recommend not storing the events in the ViewState. It will be much faster to query the database than to send the full event set back and forth with every server call.