Bug in v1.8.4 - AutoCompletion vs running query

If I use autocompletion while a query started from the same edit
window is already running, the whole application freezes until the
query is finished, and a message appears in the message page reading:
********** Error **********
The query gets committed, its results remain.
The error message does not show up in the postgresql server logs,
though the server is set up to log error messages (and other error
messages are really logged).

In fact, any query run from anywhere other than an edit window while a
query started from anywhere in the same PgAdmin instance is already
running will freeze the whole application until either of the queries
is finished. The message "********** Error **********", however, only
appears in the case described above.

client:
PgAdminIII v.1.8.4
Windows XP
server:
postgresql v8.2.7
a linux machine

Regards,
Gabor.