From Forum Nokia Wiki

In S60 3rd Edition and later SDKs, a full framework for web services is provided, allowing simplified access to SOAP services.http://www.forum.nokia.com/main/resources/technologies/web_services/index.html

You can use http to send SOAP request and use your XML parser to SOAP messages.

_LIT8(KSoapAction, "SoapAction");
_LIT8(KSoapActionParam, "http://soaptest.org/method");
 
RStringF action = iSession.StringPool().OpenFStringL(KSoapAction);
CleanupClosePushL(action);
 
RStringF param = iSession.StringPool().OpenFStringL(KSoapActionParam);
CleanupClosePushL(param);
 
RHTTPHeaders headers = iTransaction.Request().GetHeaderCollection();
 
THTTPHdrVal stringVal(param);
headers.SetFieldL(action, stringVal);