diff --git a/core/src/main/resources/org/springframework/security/config/spring-security-2.0.rnc b/core/src/main/resources/org/springframework/security/config/spring-security-2.0.rnc
index cefe55f8cd..a67234e5cf 100644
--- a/core/src/main/resources/org/springframework/security/config/spring-security-2.0.rnc
+++ b/core/src/main/resources/org/springframework/security/config/spring-security-2.0.rnc
@@ -226,6 +226,10 @@ ap.attlist &=
   ## Specifies a reference to a separately configured UserDetailsService from which to obtain authentication data.  
      attribute user-service-ref {xsd:string}?
 
+custom-authentication-provider =
+     element custom-authentication-provider {cap.attlist}
+cap.attlist &= empty
+
 user-service =
   ## Creates an in-memory UserDetailsService from a properties file or a list of "user" child elements.
     element user-service {id? & (properties-file | (user*))}
diff --git a/core/src/main/resources/org/springframework/security/config/spring-security-2.0.xsd b/core/src/main/resources/org/springframework/security/config/spring-security-2.0.xsd
index f9e6045e3c..69e70ba3c5 100644
--- a/core/src/main/resources/org/springframework/security/config/spring-security-2.0.xsd
+++ b/core/src/main/resources/org/springframework/security/config/spring-security-2.0.xsd
@@ -561,6 +561,9 @@
       </xs:annotation>
     </xs:attribute>
   </xs:attributeGroup>
+  <xs:element name="custom-authentication-provider">
+    <xs:complexType/>
+  </xs:element>
   <xs:element name="user-service">
     <xs:annotation>
       <xs:documentation>Creates an in-memory UserDetailsService from a properties file or a list of "user" child elements.</xs:documentation>