check.tpo erroneously asserts "Sorry. You are not using Tor."
Perhaps the website could be changed to add a footnote something like "[*] In rare cases your exit node may use a secondary ip address or the exit relay may not be in the consensus. To be certain you are using Tor, click Torbutton and select New Identity, then refresh your browser."
example instance: (2011-11-06 around 15h30 EDT) Your IP address appears to be: 188.8.131.52
version TBB 0.2.2.39-5 x64 linux tarball
supplementary info from irc: keb: then your current exit uses one IP for the OR Port and one for outgoing connections most probably https://atlas.torproject.org/#search/184.108.40.206 https://metrics.torproject.org/exonerator.html?targetaddr=&targetPort=&ip=220.127.116.11×tamp=2012-11-05#relay @source "18.104.22.168" router Warlboro 22.214.171.124 9001 0 9030