SignResponse::Profile attribute.

Dear all,

In section 3.2 of the core, third paragraph says:

"Profile [Optional]
This attribute indicates the particular DSS profile used by the server. 
It may be used by the
client for logging purposes or to make sure the server implements a 
profile the client expects."

It seems from this text that this attribute is optional. Nevertheless, 
in the
XML schema (in both, the core document and the .xsd file) it appears as 
required:

<xs:attribute name=”Profile” type=”xs:anyURI” use=”required”/>

Should it not be use="optional"?

Juan Carlos