Given schema definitions that define the same element differently, can one import/include both definitions and reference them independently from within a third schema definition?

For example, given:

<schema xmlns="http://www.w3.org/2001/XMLSchema"
  targetNamespace="urn:example:namespace">
    <element name="message" type="boolean"/>
</schema>

and:

<schema xmlns="http://www.w3.org/2001/XMLSchema"
  targetNamespace="urn:example:namespace">
    <element name="message" type="date"/>
</schema>

Can one construct the following:

<schema xmlns="http://www.w3.org/2001/XMLSchema"
  targetNamespace="urn:example:namespace">
    <complexType name="booleanMessageType">
        <xs:sequence>
            <!-- reference to first definition here -->
        </xs:sequence>
    </complexType>
    <complexType name="dateMessageType">
        <xs:sequence>
            <!-- reference to second definition here -->
        </xs:sequence>
    </complexType>
</schema>