Schema validation fails for xenc11:MGF

Hi all,

we are implementing a SAML based SSO framework, but the latest version of our 
software rejects validation of the xenc11:MGF element in the SAML assertion.
Using a dedicated validator tool 
(http://www.softwarebytes.org/xmlvalidation/), the error message is:

[Error] saml-test.xml:79:39:cvc-complex-type.2.4.c: The matching wildcard is 
strict, but no declaration can be found for element 'xenc11:MGF'.

The reason for this is that xenc:EncryptionMethodType allows for
   <any namespace='##other' minOccurs='0' maxOccurs='unbounded'/>
without specifying 'processContents="lax"', as most other 'any' declarations 
do. Thus the validator is requested to check the schema for  'xenc11:MGF' This 
will fail, because there is no 'import namespace' instruction for xenc11. The 
'note that optional xenc11:MGF element may be used here' in the schema comment 
is helpful for human readers, but unfortunately not fort he validator.

As I guess you do not like the idea importing xenc11 in the xenc schema, you 
should at least use 'processContents="lax" to make schema validation optional 
for this element. Otherwise schema validation has to be switched off 
completely, which is a nightmare to security aware (aka paranoid) subjects.

Greetings
Gerhard

Offending fragment in our SAML assertion:
----- 8< ---------- 8< ---------- 8< ---------- 8< -----
                    <xenc:EncryptionMethod 
Algorithm="http://www.w3.org/2001/04/xmlenc#rsa-1_5">
                        <ds:DigestMethod 
Algorithm="http://www.w3.org/2001/04/xmlenc#sha256" />
                        <xenc11:MGF
                                    xmlns:xenc11="http://www.w3.org/2009/xmlenc11#"
                                    Algorithm="http://www.w3.org/2009/xmlenc11#mgf1sha256"
                                    />
                    </xenc:EncryptionMethod>