This is the exact same issue I've been having since Feb, 2012, you can see my original post
here
Since then the only response I have received from Telerik is that they acknowledge it as an issue but cannot confirm when it will be fixed. They have also stated that they cannot suggest any workarounds. This has become a serious issue for our product to which point our management is starting to suggest looking at other scheduling components even tho we are deeply invested into the RadScheduleView.
The thing that is disappointing is that Telerik's WinForm scheduler had this exact feature.
Anyways from what I'm told, the entry in their issue tracker is
here (the description sounds different but I've been told it's the same issue) so the best thing you can do is go vote to have it fixed.