src/test/java/test/testng37/testng-37.xml

<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd" >
<suite name="TESTNG-37 Suite" verbose="2">
  <test name="TESTNG-57">
      <parameter name="notnull" value="null"/>
      <parameter name="nullvalue" value="NULL"/>
      <packages>
          <package name="test.testng37" />
      </packages>
  </test>
</suite>