masked date extender not working as expected

see code, when I go to enter a date manually i'm trying to get the mask to enter from left to right in the mm/dd/yyyy format mask.  so I want the start cursor to be at the left 'm' in mm. however it comes up in the left most 'y' of yyyy

are the other validators and extenders interfering? if so how to keep them from interfering?

<asp:CalendarExtender ID="enddate01CalExt" runat="server" TargetControlID="date01" ></asp:CalendarExtender><asp:CompareValidator id="enddate01DateValid" runat="server" Type="Date" Operator="DataTypeCheck"
    ControlToValidate="date01" ErrorMessage="date is not valid" display="Dynamic" CssClass="errorMsg"></asp:CompareValidator><asp:CompareValidator ControlToCompare="begdate01" Type="Date" ControlToValidate="date01" ID="enddate01DateCompare"
     runat="server" Operator="GreaterThan" ErrorMessage="end date must be greater than begin date" Display="Dynamic" CssClass="errorMsg"></asp:CompareValidator><asp:MaskedEditExtender Mask="mm/dd/yyyy" MaskType="Date" UserDateFormat="MonthDayYear" InputDirection="LeftToRight"
     TargetControlID="date01" runat="server"></asp:MaskedEditExtender><asp:MaskedEditValidator ControlToValidate="date01" runat="server" SetFocusOnError="true" ></asp:MaskedEditValidator>