Would following work for you?

loHeaderHandler=CreateObject("SessionInfoClient.ClientHeaderHandler")
loUniversalThread.AddProperty('HeaderHandler',loHeaderHandler)

>I have the following in VB:
>
>

>Set sc = WScript.CreateObject("MSSOAP.SoapClient")
>sc.mssoapinit "http://www.levelextreme.com/universalthread.wsdl"
>set sc.HeaderHandler = WScript.CreateObject("SessionInfoClient.ClientHeaderHandler")
>

>
>I tried to convert that in VFP with:
>
>

>loUniversalThread=Createobject("mssoap.soapclient")
>loUniversalThread.mssoapinit("http://www.levelextreme.com/universalthread.wsdl")
>loHeaderHandler=CreateObject("SessionInfoClient")
>loUniversalThread.AddObject('HeaderHandler','loHeaderHandler')
>

>
>But this doesn't work as the last line says unknown name.