Microsoft-IIS / 8.5，Oracle输出变量被截断

OracleConnection connection = DBHelper.OracleConnection;
OracleCommand OraCommand = connection.CreateCommand();

OraCommand.CommandText = "AUTHENTICATION.Authenticate";
OraCommand.CommandType = CommandType.StoredProcedure;

int zero = 0;
OracleParameter newParam = null;


OraCommand.Parameters.Add(newParam);
newParam = new OracleParameter("Authenticated", OracleType.VarChar);
newParam.Direction = ParameterDirection.Output;
newParam.Size = 4000;


OraCommand.Parameters.Add(newParam);
newParam = new OracleParameter("Message", OracleType.VarChar);
newParam.Direction = ParameterDirection.Output;
newParam.Size = 4000;
OraCommand.Parameters.Add(newParam);


newParam = new OracleParameter("Response", OracleType.VarChar);
newParam.Direction = ParameterDirection.Output;
newParam.Size = 4000;
OraCommand.Parameters.Add(newParam);

try
{
        connection.Open();
        OraCommand.ExecuteNonQuery();
        connection.Close();

        errorLabel.Text = OraCommand.Parameters["Message"].Value.ToString() ;

        if (OraCommand.Parameters["Authenticated"].Value.ToString() == "Yes")
        {


            this.Response.Redirect("Default.aspx", true);
        }else
        {
            errorLabel.Text = OraCommand.Parameters["Message"].Value.ToString() + Request.ServerVariables["SERVER_SOFTWARE"] + OraCommand.Parameters[9].Value.ToString();
        }

    }
    catch (Exception ex)
    {
        errorLabel.Text = ex.ToString();
    }
OracleConnection connection = DBHelper.OracleCo