Extending a Complextype - with xsd:all

[<binu.idicula@wipro.com>]

Hi All,
   I have a complextype already like this
	<xsd:complexType name="MyIdentifier ">
		<xsd:all>
			<xsd:element name="firstname" type="xsd:string"
/>
			<xsd:element name="dateofbirth" type="xsd:date"
/>
		</xsd:all>
		<xsd:attribute name="lastname" type="xsd:string"
use="required" />
	</xsd:complexType>

Is it possible to extend this with xsd:complexcontent and xsd:all. I
have to add 2 more elements, out of which 1 is optional.

Thank you in advance
Regards
Binu K Idicula

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