Question about the SOAP 1.2 envelope schema

Hi,

I've been looking at the SOAP 1.2 Envelope schema[1], I don't beleive that the schema as it stands allows for the encodingStyle attribute to appear on the Envelope or Header elements, whilst the prose allow for that situation, however my understanding of XSD is shakey enough that i could be wrong. Shouldn't the Envelope and Header complex types include an attributeGroup reference to the encodingStyle attribute group ? Also is there any reason why encodingStyle uses an attribute group ?

Thanks
Simon
www.pocketsoap.com
[1] http://www.w3.org/2001/12/soap-envelope