Response Group SignIn/SignOut

I need to be able to allow Lync users acting as telephony agents to dynamically select which queue response groups they are signed into. We know this functionality exists because Lync Client users can do it from the "Response Group Settings" menu which invokes a web page ((https://<web_pool FQDN>/RgsClients/Tab.aspx.)

I have posted this question in many forums over the last 6 months and each time been told to try a different forum.

I know that the methods I want exist, these are the WSDL definitions for the Lync 2010 RgsAgentService.

        Public Function SignIn(ByVal groupId As System.Guid) As Boolean
            Dim results() As Object = Me.Invoke("SignIn", New Object() {groupId})
            Return CType(results(0),Boolean)
        End Function
        Public Function SignOut(ByVal groupId As System.Guid) As Boolean
            Dim results() As Object = Me.Invoke("SignOut", New Object() {groupId})
            Return CType(results(0),Boolean)
        End Function

However I have not managed to get anywhere with trying to get the web interface to work, so what I would like to know is, is this functionality available via the UCMA ?

Thanks.