public IGroup CreateAndAdd(string groupName, string groupEmailAdress)
        {
            const string CREATE_GROUP =
                @"<ADMINISTRATION><PROJECT guid=""{0}"" action=""assign""><GROUPS action=""addnew""><GROUP name=""{1}"" email=""{2}""/></GROUPS></PROJECT></ADMINISTRATION>";

            var xmlDoc = Session.ExecuteRQL(CREATE_GROUP.SecureRQLFormat(_project, groupName, groupEmailAdress));

            var groupGuid = xmlDoc.GetSingleElement("GROUP").GetGuid();

            InvalidateCache();
            return(GroupFactory.CreateFromGuid(Session, groupGuid));
        }