Current JDBC Driver char encoding - Bug or feature?

Hello Postgres & JDBC gurus,

We recently upgraded from jdbc7.0-1.2.jar to jdbc7.1-1.2.jar and now non-
ASCII characters display as ?. That was not the case with the old driver.

Our Postgres Installation was built with --enable-locale but not with
--enable-multibyte or anything else differing from the default config.

psql displays that characters correctly when printing query results.

Any hints what we can do about this?

Can't imagine that I have to reconfigure the backend when the JDBC driver
changes.
We can't fall back to the old driver because of various other bugs or
unimplemented methods there.

Please forgive if that issue was discussed already, I really tried to
find related messages, but...

TIA, jan

--
Jan Wessely
Vienna Knowledge Net
mailto:jawe(at)vknn(dot)org
http://www.vknn.org