xml xsd element restriction using another element

Question

I am wondering if there is a way to restrict what validates using one element to check another element. In the example below, is it possible to check a restriction that if OptionOne is selected as "B", then RefIssue will have to be selected as "XXXX-B-XXX" and vice versa?

I have looked into key / refkey, but I was not able to figure out if it could do this constraint. Any help appreciated.

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified">
  <xs:element name="CustomIssueSchema">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="CustomIssue" maxOccurs="unbounded">
          <xs:complexType>
            <xs:sequence>
              <xs:element name="CustomArgs" maxOccurs="unbounded">
                <xs:complexType>
                  <xs:sequence>
                    <xs:element name="OptionOne">
                      <xs:simpleType>
                        <xs:restriction base="xs:string">
                          <xs:enumeration value="A"/>
                          <xs:enumeration value="B"/>
                          <xs:enumeration value="C"/>
                        </xs:restriction>
                      </xs:simpleType>
                    </xs:element>
                  </xs:sequence>
                </xs:complexType>
              </xs:element>
              <xs:element name="CustomRef" maxOccurs="unbounded">
                <xs:complexType>
                  <xs:sequence>
                    <xs:element name="RefIssue">
                      <xs:simpleType>
                        <xs:restriction base="xs:string">
                          <xs:enumeration value="XXXX-A-XXX"/>
                          <xs:enumeration value="XXXX-B-XXX"/>
                          <xs:enumeration value="XXXX-C-XXX"/>
                        </xs:restriction>
                      </xs:simpleType>
                    </xs:element>
                  </xs:sequence>
                </xs:complexType>
              </xs:element>
            </xs:sequence>
          </xs:complexType>
        </xs:element>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
</xs:schema>

Answer 1

This is not possible in XML schema. You cannot have cross-element constraints of this sort, you will have to use another language (Schematron, XQuery, etc) or write code.

Answer 2

looks like you can do it with XSD 1.1, but it is not released and there are no implementations of it I can use.