SOAP NPE Error

I'm using a wsdl to set up my web service.  However, whenever I try and run
any methods from the client, I get a NPE returned.  The method on the server
is the default empty stub.  This is the soap message that I'm sending.  

<?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
 <soapenv:Body>
  <nsl:addClientToMCUConnection
soapenv:encodingStyle="http://schemas.xml.soap.org/soap/encoding/"
xmlns:nsl="urn:com.saic.dcts.nci.websvc">
   <spaceID xsi:type="xsd:int">42</spaceID>
   <clientIP xsi:type="xsd:string">10.0.0.1</clientIP>
   <mcuIP xsi:type="xsd:string">10.0.0.2</mcuIP>
  </nsl:addClientToMCUConnection>
 </soapenv:Body>
</soapenv:Envelope>

TIA for any help.

Chris