How to generate SOAP request without Header element

It looks like server I have to call is buggy and I noticed, if I remove empty SOAP Header from request it works fine - othervise fails.
How to generate soapRequest without Header?

Example:
This works fine:
<soapenv:Envelope xmlns:soapenv=“http://schemas.xmlsoap.org/soap/envelope/” xmlns:fus=“http://localhost/FusionBOWS/FusionBOWS.xsd”>
soapenv:Body
fus:Query

</fus:Query>
</soapenv:Body>
</soapenv:Envelope>

This not:
<soapenv:Envelope xmlns:soapenv=“http://schemas.xmlsoap.org/soap/envelope/” xmlns:fus=“http://localhost/FusionBOWS/FusionBOWS.xsd”>
soapenv:Header/
soapenv:Body
fus:Query

</fus:Query>
</soapenv:Body>
</soapenv:Envelope>

(I use WebMethods IS to call Frontrange service)

Solved.
I had to manualy pepare SOAP request and use pub.client.http service.
Works fine.

Regards