[Bakai Madybaev]

Ставил этот скрипт на поле ownerid, событие onChange:

var ownerLookupItem = new Array;
ownerLookupItem = crmForm.all.ownerid.DataValue;
var lookupData = new Array();
var bUnitLookupItem= new Object();

if (ownerLookupItem != null)
{
  if (ownerLookupItem[0] != null)
  {
    var oXmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
    sGUID=ownerLookupItem[0].id;
    if (sGUID != null)
    {
      var sEntityName="systemuser";
      var sAttributeName="businessunitid";
      
      var bUID ="";
      
      bUID = GetAttributeValue(sEntityName, sGUID, sAttributeName);
      
      var bUEntityName ="businessunit";
      var bUEntityType ="name";
       
      var bUName = GetAttributeValue(bUEntityName, bUID, bUEntityType);
      
      bUnitLookupItem.id = bUID;
      bUnitLookupItem.typename = bUEntityName;
      bUnitLookupItem.name = bUName;
      
      lookupData[0] = bUnitLookupItem;
      crmForm.all.new_businessunit_incident.DataValue = lookupData;
      }
  }
}
function GetAttributeValue(sEntityName, sGUID, sAttributeName)
{
  var xml = "";
    xml +="<?xml version=\"1.0\" encoding=\"utf-8\"?>";
    xml +="<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\">";
    xml += GenerateAuthenticationHeader();
    xml +="<soap:Body>";
    xml +="<entityName xmlns=\"http://schemas.microsoft.com/crm/2006/WebServices\">" + sEntityName + "</entityName>";
    xml +="<id xmlns=\"http://schemas.microsoft.com/crm/2006/WebServices\">" + sGUID + "</id>";
    xml +="<columnSet xmlns=\"http://schemas.microsoft.com/crm/2006/WebServices\" xmlns:q=\"http://schemas.microsoft.com/crm/2006/Query\" xsi:type=\"q:ColumnSet\">"; 
    xml +="<q:Attributes>";
    xml +="<q:Attribute>" + sAttributeName + "</q:Attribute>";
    xml +="</q:Attributes>";
    xml +="</columnSet>";
    xml +="</soap:Body>";
    xml +="</soap:Envelope>";
    var xmlHttpRequest = new ActiveXObject("Msxml2.XMLHTTP");
    xmlHttpRequest.Open("POST", "/mscrmservices/2006/CrmService.asmx", false);
    xmlHttpRequest.setRequestHeader("SOAPAction","http://schemas.microsoft.com/crm/2006/WebServices/Retrieve");
    xmlHttpRequest.setRequestHeader("Content-Type", "text/xml; charset=utf-8");
    xmlHttpRequest.setRequestHeader("Content-Length", xml.length);
    xmlHttpRequest.send(xml);
 
    var doc = xmlHttpRequest.responseXML;

    var retValue = "";
    if (doc.selectSingleNode("//RetrieveResult/q1:" + sAttributeName) != null) 
      retValue = doc.selectSingleNode("//RetrieveResult/q1:" + sAttributeName).text;

    return retValue;
}