To my regret we discovered this problem recently and could not manage to fix it for the official Q2 version scheduled for the beginning of the next week. We will try to fix it for one of the internal builds after the release or for the SP1.
As a workaround you can try to set again the Source property of the dataPager in case you have canceled the event:
sender, Telerik.Windows.Controls.PageIndexChangingEventArgs e)
dataPager.Source = Person.GetPeople();
the Telerik team
Do you want to have your say when we set our development plans?
Do you want to know when a feature you care about is added or when a bug fixed?
Telerik Public Issue Tracking
system and vote to affect the priority of the items