Also I just discovered that this problem only occurs when setting MultiviewColumns="2". Here is my Markup:
<telerik:RadCalendar ID="rcalDateRange" runat="server" EnableEmbeddedSkins="false"
EnableEmbeddedBaseStylesheet="false" Skin="swOffice2007" ShowRowHeaders="False"
MultiViewColumns="2" UseColumnHeadersAsSelectors="false" EnableMultiSelect="true"
AutoPostBack="true" Visible="true" ShowOtherMonthsDays="false" EnableMonthYearFastNavigation="false">
<ClientEvents OnDateClick="rcalDateRange_DateClick" OnCalendarViewChanging="rcalDateRange_ViewChanging" />
</telerik:RadCalendar>
Any suggestions on how to fix this?