Textbox with binding value and date of birth format masked edit control

gurus,
i have a textbox inside the formview edittemplate.  my problem is i want to bind textbox with "date_of_birth" field from database while page load as 05/05/1977 format, if there is no data then i want to display as __/__/__/ Masked for dob format, Can you somebody help me on this ?
Thanks
Kevin
<asp:FormView ID="fvReport" runat="server" Width="100%"> <EditItemTemplate> <div class="form_item"> <label>Date of Birth</label> <asp:textbox ID="txtDOB" runat="server" DateFormat="MM/dd/yyyy" DisplayDateFormat="MM/dd/yyyy" Text='<%# Bind("date_of_birth", "{0:MM/dd/yyyy}")%>' CssClass="text_box"> ..... </EditItemTemplate> </asp:FormView> < ...