SOAP Headers in .NET VB

Hi !

I am developing a client for a web service using
Visual Studio .NET VB. In order to use the web service
one is supposed to include a soap header in some calls
including a session id.
These soap headers are not defined
as in all examples regarding using soap headers for web
services developed using .NET. This means that there are
no soap header classes available when using VB or any
member variables like MyService.MyHeader to be set in
any web service.

Is it possible to set a header for a call in the client
in some other way or do I have to use some other means of
creating my client other then .NET ?

regards Niklas