[2008] Details DataFormatString

[nmadd]

I know Google lights up like a Christmas tree when you search for something regarding date format in ASP.NET but I'm still having a problem with a BoundField and formatting its date.

ExpiryDate is varchar2(4000) in dd/mm/yyyy format.
SQL (Oracle 9i):

select
  ag.AGREEMENTS_ABBR LicensorNumber,
  (select r1.FIELD_VALUE
  from V_REPCUSTOMFIELDDATA r1
  where
    r1.INTERNAL_DESCRIPTIONS_CODE = 21
    and r1.ASSOCIATED_WITH_CODE = ag.AGREEMENTS_ABBR) ContractName,
  ag.AGREEMENTS_NAME ProjectName,
  ag.AGREEMENTS_AVAILDATE AvailableDate,
  to_date(ag.AGREEMENTS_EXPLEXPIRES, 'dd/mm/yyyy') ExpiryDate,
  (select to_date(r2.FIELD_VALUE, 'dd-mon-yyyy')
  from V_REPCUSTOMFIELDDATA r2
  where
    r2.INTERNAL_DESCRIPTIONS_CODE = 35
    and r2.ASSOCIATED_WITH_CODE = ag.AGREEMENTS_ABBR) SellOffDate,
  ag.FREQ_DISPLAY ReportFrequency 
from V_AGREEMENT ag
where ag.AGREEMENTS_ABBR = :licensorNum

DetailsView:

        <asp:DetailsView ID="DetailsView1" runat="server" AutoGenerateRows="False">
            <Fields>
                <asp:BoundField DataField="LicensorNumber" HeaderText="Licensor Number" />
                <asp:BoundField DataField="ProjectName" HeaderText="Project Name" />
                <asp:BoundField DataField="AvailableDate" 
                    DataFormatString="{0:MM/dd/yyyy}" HeaderText="Start Date" 
                    HtmlEncode="False" />
                <asp:BoundField DataField="ExpiryDate" 
                    DataFormatString="{0:MM/dd/yyyy}" HeaderText="Expiry Date" 
                    HtmlEncode="False" />
                <asp:BoundField DataField="SellOffDate" HeaderText="Sell Off Date" 
                    DataFormatString="{0:MM/dd/yyyy}" 
                    HtmlEncode="False" />
                <asp:BoundField DataField="ReportFrequency" HeaderText="Reporting Frequency" />
            </Fields>
        </asp:DetailsView>

SellOffDate (also a varchar2(4000)) appears formatted correctly in my DetailsView. ExpiryDate appears formatted as "12/31/99 12:00:00AM" in my Details View.

What simple thing am I missing this time?

EDIT: Please note that I cannot change the Data Types in the database.
EDIT2: Nuts - meant to say DetailsView in the title, of course.