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Anonymous
Those who are interested in the &quot;pingable&quot; attribute might want to know that in the meantime the document has become an RFC (Standards Track):<br /><br /><a href="http://www.rfc-editor.org/rfc/rfc5943.txt" rel="nofollow">http://www.rfc-editor.org/rfc/rfc5943.txt</a><br /><br />Robert<br />