[a33ik]

Попробуйте такой.

В принципе учёл варианты создания/изменения. Тут уже дело за Вами. Тестируйте. По идее всё честно.

if (crmForm.all.new_invoice.DataValue != null)
{
	var xml = "<?xml version='1.0' encoding='utf-8'?>"+ 
	"<soap:Envelope xmlns:soap='http://schemas.xmlsoap.org/soap/envelope/'"+
	" xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'"+
	" xmlns:xsd='http://www.w3.org/2001/XMLSchema'>"+ 
	GenerateAuthenticationHeader()+ 
	"<soap:Body>"+ 
	"<RetrieveMultiple xmlns='http://schemas.microsoft.com/crm/2007/WebServices'>"+ 
	"<query xmlns:q1='http://schemas.microsoft.com/crm/2006/Query'"+
	" xsi:type='q1:QueryExpression'>"+ 
	"<q1:EntityName>new_payment</q1:EntityName>"+ 
	"<q1:ColumnSet xsi:type='q1:ColumnSet'>"+ 
	"<q1:Attributes>"+ 
	"<q1:Attribute>new_summ</q1:Attribute>"+ 
	"</q1:Attributes>"+ 
	"</q1:ColumnSet>"+ 
	"<q1:Distinct>false</q1:Distinct>"+ 
	"<q1:Criteria>"+ 
	"<q1:FilterOperator>And</q1:FilterOperator>"+ 
	"<q1:Conditions>"+ 
	"<q1:Condition>"+ 
	"<q1:AttributeName>new_invoice</q1:AttributeName>"+ 
	"<q1:Operator>Equal</q1:Operator>"+ 
	"<q1:Values>"+ 
	"<q1:Value xsi:type='xsd:string'>"+crmForm.all.new_invoice.DataValue[0].id+"</q1:Value>"+ 
	"</q1:Values>"+ 
	"</q1:Condition>";

	if (crmForm.FormType != 1)
	{
		xml = xml + "<q1:Condition>"+ 
		"<q1:AttributeName>new_paymentid</q1:AttributeName>"+ 
		"<q1:Operator>NotEqual</q1:Operator>"+ 
		"<q1:Values>"+ 
		"<q1:Value xsi:type='xsd:string'>" + crmForm.ObjectId + "</q1:Value>"+ 
		"</q1:Values>"+ 
		"</q1:Condition>";
	}

	xml = xml + "</q1:Conditions>"+ 
	"</q1:Criteria>"+ 
	"</query>"+ 
	"</RetrieveMultiple>"+ 
	"</soap:Body>"+ 
	"</soap:Envelope>";

	var xHReq = new ActiveXObject("Msxml2.XMLHTTP");
	xHReq.Open("POST", "/mscrmservices/2007/CrmService.asmx", false);
	xHReq.setRequestHeader("SOAPAction","http://schemas.microsoft.com/crm/2007/WebServices/RetrieveMultiple");
	xHReq.setRequestHeader("Content-Type", "text/xml; charset=utf-8");
	xHReq.setRequestHeader("Content-Length", xml.length);
	xHReq.send(xml);

	var resultXml = xHReq.responseXML;

	if (results.length != 0)
	{
		var summa = 0
		for (i=0;i < results.length;i++)
		{
			summa = summa + parseFloat(results[i].selectSingleNode('./q1:new_summ') == null ? 0 :results[i].selectSingleNode('./q1:new_summ').nodeTypedValue); 
		}

		if (crmForm.all.new_summ.DataValue != null)
			summa = summa + crmForm.all.new_summ.DataValue;

		var xml = "<?xml version='1.0' encoding='utf-8'?>"+ 
		"<soap:Envelope xmlns:soap='http://schemas.xmlsoap.org/soap/envelope/'"+
		" xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'"+
		" xmlns:xsd='http://www.w3.org/2001/XMLSchema'>"+ 
		GenerateAuthenticationHeader()+ 
		"<soap:Body>"+ 
		"<Update xmlns='http://schemas.microsoft.com/crm/2007/WebServices'>"+ 
		"<entity xsi:type='invoice'>"+ 
		"<ec_totalpayment>"+atr+"</ec_totalpayment>"+ 
		"<invoiceid>"+crmForm.all.new_invoice.DataValue[0].id+"</invoiceid>"+ 
		"</entity>"+ 
		"</Update>"+ 
		"</soap:Body>"+ 
		"</soap:Envelope>";

		var xHReq = new ActiveXObject("Msxml2.XMLHTTP");
		xHReq.Open("POST", "/mscrmservices/2007/CrmService.asmx", false);
		xHReq.setRequestHeader("SOAPAction","http://schemas.microsoft.com/crm/2007/WebServices/Update");
		xHReq.setRequestHeader("Content-Type", "text/xml; charset=utf-8");
		xHReq.setRequestHeader("Content-Length", xml.length);
		xHReq.send(xml);
	}
}