TestNG bug: When running TestNG programmatically, child xml suites are not run (when added using setSuiteFIles())

FastTest.java

import org.testng.ITestContext;
import org.testng.annotations.BeforeMethod;
import org.testng.annotations.Test;

public class FastTest {
	ITestContext context;

	@BeforeMethod
	public void setup(ITestContext context) {
		this.context = context;
	}

	@Test
	public void test1() {
		System.out.println("Now Running: " + context.getSuite().getName()
				+ ", FastTest");
		try {
			Thread.sleep(1000);
		} catch (InterruptedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

Suite1.xml

<?xml version="1.0" encoding="UTF-8"?> 
<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd"> 
<suite name="Suite 1"> 
  <test name="FastTest1" preserve-order="false"> 
    <classes> 
      <class name="FastTest"/> 
    </classes> 
  </test> 
</suite> 

testng.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd">
<suite verbose="2" name="TestNG XML File Suite">
  <suite-files>
    <suite-file path="./Suite1.xml"/>
  </suite-files>
  <test name="Test 1" preserve-order="true">
    <classes>
      <class name="FastTest"/>
    </classes>
  </test> <!-- Test 1 -->
</suite> <!-- Programmatic XmlSuite -->
            

TestRunner.java

import java.util.Arrays;
import org.testng.TestNG;
import org.testng.xml.*;

public class TestRunner {

	static TestNG testng;

	public static void main(String[] args) {

		try {
			testng = new TestNG();
			testng.setPreserveOrder(true);
			testng.setVerbose(2);

			// create a suite programmatically
			XmlSuite suite = new XmlSuite();
			suite.setName("Programmatic XmlSuite");

			// create a test case for the suite
			XmlTest xmltest = new XmlTest(suite);
			xmltest.setName("Test 1");
			xmltest.setXmlClasses(Arrays.asList(new XmlClass("FastTest")));

			// add a suite-file to the suite
			suite.setSuiteFiles(Arrays.asList("./Suite1.xml"));

			// 1. To run with testng.xml file, uncomment this one, comment 2
			// testng.setTestSuites(Arrays.asList("testng.xml"));

			// 2. to run with XmlSuite, uncomment this one, comment 1
			testng.setXmlSuites(Arrays.asList(suite));

			testng.run();
		} catch (Exception e1) {
			e1.printStackTrace();
		}

	}
}