valid data-types?

Hi,

    <xsd:simpleType name="fixed.14.4">
        <xsd:restriction base="xsd:decimal">
            <xsd:scale value="4"/>
            <xsd:precision value="18"/>
            <xsd:pattern value="(\+|-)?\d{0,14}(\.d{0,4})"/>
        </xsd:restriction>
    </xsd:simpleType>

    <xsd:simpleType name="datetime">
        <xsd:restriction base="xsd:timeInstant">
             <xsd:pattern
value="\d{4,4}\-\d{2,2}-\d{2,2}T\d{2,2}:\d{2,2}:\d{2,2}"/>
        </xsd:restriction>
    </xsd:simpleType>


here scale/timeInstant is being used as a restriction facet.Is this part of
the http://www.w3.org/2001/XMLSchema or is a recent addition?

Regards,
Shadab