Siebel EAI invocation through VBA

We want to post XML messages to Siebel EAI ObjMgr through SiebelQuery and SiebelUpsert methods of the EAI in form of

SWEExtSource=SiebelUpsert&SWEExtCmd=Execute&UserName=PRASADBD&Password=PRASADBD@1&SWEExtData=

We want to do this through VBA code as below

Dim httpTarget As New MSXML2.XMLHTTP

Dim strUID As String

Dim strPWD As String

strURL_ExecInline = "http://10.88.35.79:6100/eai_enu/start.swe?"

strUID = "PRASADBD"

strPWD = "PRASADBD@1"

httpTarget.Open "POST", strURL_ExecInline, False

httpTarget.setRequestHeader "Content-type", "application/x-www-form-urlencoded"

strReqNew = "SWEExtSource=SiebelUpsert&SWEExtCmd=Execute&UserName=" & strUID & "&Password=" & strPWD & "&SWEExtData="

strReqNew = strReqNew & "<?xml version='1.0' encoding='UTF-8'?><?Siebel-Property-Set EscapeNames='false'?>"

strReqNew = strReqNew & strRequest