Problem with Element Definition and XML CDATA

Hello all!

If this message is a duplicate, I sincerely apologize. I searched through the archives and could not find an answer to my question, which is:

Can I define an element to contain a string OR a CDATA section, and not contain an empty string? In a schema, is there any way to allow an element to contain CDATA? I couldn't find it in the specification.

My problem: When I use an element definition and set it to a string datatype with a minimum length of 1, I get a validation error when it contains a CDATA section. I want to allow a string or a CDATA section as valid content for the same element, and I do not want to allow it to be blank.

Here are examples of what I want to allow:
    <description>some text or numbers 1234</description>
    <description><![CDATA[anything in the CDATA section]]></description>

Here is an example of what I do NOT want to allow:
    <description></description>

I tried this, which works for a string, but tells me that a CDATA section is invalid:
    <xsd:element name="description">
      <xsd:simpleType>
        <xsd:restriction base="xsd:string">
          <xsd:minLength value="1"/>
        </xsd:restriction>
      </xsd:simpleType>
    </xsd:element>

Is it possible to define this combination for an element in a schema?

Thanks,

- Matt