on PC do: 
$> wireshark -k -i <(ssh -l root IroN900 tshark -w - -i phonet0 )
where IroN900 is your IP of N900, and you'll need proper ssh pubkeys 

the isi.so has to go to your wireshark/plugins/, wherever that is
-- hint: $> find /usr/lib -name parlay.so

the isi.so are for 32/64 linux resp (see filename), built against wireshark1.4.4, other versions may or may not work.

courtesy Klaus mrmoku Kurzmann and Gnutoo