--- a/2.0/core/schema/xsd/XForms-20-Schema.xsd	Thu May 24 14:39:11 2012 +0200
+++ b/2.0/core/schema/xsd/XForms-20-Schema.xsd	Thu May 24 14:46:04 2012 +0200
@@ -164,6 +164,7 @@
 			</xsd:sequence>
 			<xsd:attributeGroup ref="xforms:Common.Attributes"/>
 			<xsd:attribute name="nodeset" type="xforms:XPathExpression" use="optional"/>
+			<xsd:attribute name="ref" type="xforms:XPathExpression" use="optional"/>
 			<xsd:attribute name="calculate" type="xforms:XPathExpression" use="optional"/>
 			<xsd:attribute name="type" type="xsd:QName" use="optional"/>
 			<xsd:attribute name="required" type="xforms:XPathExpression" use="optional"/>
@@ -860,6 +861,7 @@
                             </xsd:simpleType>
                     </xsd:attribute>
                     <xsd:attribute name="nodeset" type="xforms:XPathExpression" use="optional"/>
+                    <xsd:attribute name="ref" type="xforms:XPathExpression" use="optional"/>
         					</xsd:complexType>
         				</xsd:element>
 				</xsd:choice>