Exporting XML from Excel and Keeping Date Format
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<dataroot>
    <Tabelle11>
        <Title_1>2009-10-12T00:00:00.000</Title_1>
        <Title_2>40098</Title_2>
    </Tabelle11>
    <Tabelle11>
        <Title_1>2000-01-01T00:00:00.000</Title_1>
        <Title_2>36526</Title_2>
    </Tabelle11>
</dataroot>

<xsd:element name="Title_1" minOccurs="0" od:jetType="datetime" od:sqlSType="datetime" type="xsd:dateTime">
    <xsd:annotation>
        <xsd:appinfo>
            <od:fieldProperty name="Format" type="10" value="dd.mm.yyyy"/>
        </xsd:appinfo>
    </xsd:annotation>
</xsd:element>
<xsd:element name="Title_2" minOccurs="0" od:jetType="text" od:sqlSType="nvarchar">
    <xsd:annotation>
        <xsd:appinfo>
            <od:fieldProperty name="Format" type="10" value="@"/>
        </xsd:appinfo>
    </xsd:annotation>
    <xsd:simpleType>
        <xsd:restriction base="xsd:string">
            <xsd:maxLength value="255"/>
        </xsd:restriction>
    </xsd:simpleType>
</xsd:element>