Siebel - ATG User Registration Integration using Siebel Reference Module is giving Error

Urgent Help is needed to resolve the following issue which is stopping me to integrate User Registration in Siebel

<SOAP-ENV:Body>

<SOAP-ENV:Fault>

<faultcode>SOAP-ENV:Server</faultcode>

<faultstring>Error while processing argument http://www.siebel.com/SelfService/Common/Contact/Data:ListOfSSContact

for operation SelfServiceContactExecute(SBL-EAI-04316)</faultstring>

<detail>

<siebelf:siebdetail xmlns:siebelf="http://www.siebel.com/ws/fault">

<siebelf:logfilename>EAIObjMgr_enu_0037_38797371.log</siebelf:logfilename>

<siebelf:errorstack>

<siebelf:error>

<siebelf:errorcode>SBL-EAI-04316</siebelf:errorcode>

<siebelf:errorsymbol>IDS_EAI_WS_PROCESS_OP_ARG</siebelf:errorsymbol>

<siebelf:errormsg>Error while processing argument http://www.siebel.com/SelfService/Common/Contact/Data:ListOfSSContact

for operation SelfServiceContactExecute(SBL-EAI-04316)</siebelf:errormsg>