Openfire is sending two unavailable packets after leaving the room

Debug XML output from Exodus after quiting the room:

[2009-08-13 13:24:05.718] SENT: <presence to="test@conference.wroot/john_doe" type="unavailable"><c ext="xhtml-im" node="http://exodus.jabberstudio.org/caps" ver="0.10.0.0" xmlns="http://jabber.org/protocol/caps"/><priority>0</priority></presence>
[2009-08-13 13:24:05.734] RECV: <presence to="john@wroot/WROOT" from="test@conference.wroot/john_doe" type="unavailable"><c xmlns="http://jabber.org/protocol/caps" ext="xhtml-im" node="http://exodus.jabberstudio.org/caps" ver="0.10.0.0"/><priority>0</priority><x xmlns="http://jabber.org/protocol/muc#user"><item jid="john@wroot/WROOT" affiliation="none" role="none"/></x></presence>
[2009-08-13 13:24:05.734] RECV: <presence to="john@wroot/WROOT" from="test@conference.wroot/john_doe" type="unavailable"><c xmlns="http://jabber.org/protocol/caps" ext="xhtml-im" node="http://exodus.jabberstudio.org/caps" ver="0.10.0.0"/><priority>0</priority><x xmlns="http://jabber.org/protocol/muc#user"><item jid="john@wroot/WROOT" affiliation="none" role="none"/></x></presence>