But the connector is configures individually and I specify the encoding by the configuration string sat in the JDBC driver. this string sets the encoding, but apparently it does not work.
Tje letters you are typing are from Danish, but any will do.
Now im working abit from memory, but when the databse is build, initdb is using UNICODE as encoding, "C" for locale, so it should be independant of the locale settings.
I believe the problem, as Hiroshi Saito pointed out, is that the client encoding is being set on Windows before the connection is attempted and that it is picking the wrong one. Per his post pgAdmin and JDBC are probably just starting with UTF8 and that is why they succeed. At this point I don't know how to get around that.