Havin given it some more thought (its more interesting than actually revising for the cert., which is what I should be doing)
I think you may be confusing the actual Header element with its children - the Header element needs to be in the "http://schemas.xmlsoap.org/soap/envelope/" namespace.
The children of the Header element need to be in some other namespace - at first I thought they couldn't be in the default namespace, but having tried the following it seems they can, I guess the default namespace isn't 'null', whatever null means in the context of namespaces.
(I'm using architag xml editor to experiment with schemas with
http://www.architag.com/xray/ )
[ March 21, 2007: Message edited by: michael warren ]
[ March 21, 2007: Message edited by: michael warren ]