 a default has not yet been
 setup, a new Session object is created and installed as the 
 default. <p>

 Note that a default session created with no Authenticator is
 available to all code executing in the same Java virtual
 machine, and the session can contain security sensitive
 information such as user names and passwords.</div>
<dl>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>props</code> - Properties object. Used only if a new Session
                        object is created.<br>
 