Error message while connecting to a UNICODE db

Dear friends,

while testing things for hiroshi, I found this problem on my installation:
(I read the FAQ and BUGS.txt, but as you know I'm not a good reader and
I always need to wash my eyes... :p)
pgsql server 7.3.4 with db created in "UNICODE".
pgadmin3 latest snapshot (today's one)
Observed on debian stable and unstable

When I connect to the db, I have a popup window telling me that "An
Error occured".
On the console I can see this warning:
** (pgadmin3:24606): WARNING **: Invalid UTF8 string passed to
pango_layout_set_text()

And here is pgadmin3 log file:
2003-11-26 19:25:37 INFO   : Destroying a connect dialogue
2003-11-26 19:25:37 STATUS : Connecting to database...
2003-11-26 19:25:37 INFO   : Creating pgConn object
2003-11-26 19:25:37 INFO   : Server name: 192.169.0.254 (resolved to:
192.169.0.254)
2003-11-26 19:25:37 INFO   : Opening connection with connection string:
hostaddr='192.169.0.254' dbname='template1' user='xxx' password='yyy'
port=5432
2003-11-26 19:25:37 QUERY  : Set query (192.169.0.254:5432): SELECT
pg_encoding_to_char(encoding) AS encoding, datlastsysoid
  FROM pg_database WHERE datname='template1'
2003-11-26 19:25:37 INFO   : Creating pgSet object
2003-11-26 19:25:37 INFO   : Setting client_encoding to 'UNICODE'
2003-11-26 19:25:37 ERROR  :
?????????????????????????????????????????????????????????????????????????????????????????????????????????T

(the final '?' are not mine... they are in the logfile).

If it's a known issue, just tell me to go to bed (I promise, I'll do it)!

Any idea ?

Regards,
Raphaël