soap fault: In valid string sufix

Hi Every one

My message is getting processed in Xi when it tries to send it to the legay system I get the following error.

Any ans plz....

SAP:Error xmlns:SAP="http://sap.com/xi/XI/Message/30" xmlns:SOAP="http://schemas.xmlsoap.org/soap/envelope/" SOAP:mustUnderstand="1">

<SAP:Category>XIAdapter</SAP:Category>

<SAP:Code area="PARSING">ADAPTER.SOAP_EXCEPTION</SAP:Code>

<SAP:P1 />

<SAP:P2 />

<SAP:P3 />

<SAP:P4 />

<SAP:AdditionalText>soap fault: In valid string sufix</SAP:AdditionalText>

<SAP:ApplicationFaultMessage namespace="" />

<SAP:Stack />

<SAP:Retry>M</SAP:Retry>

</SAP:Error>

Thanks