JerseyUriBuilder encoding behavior changes in release 2.20. I detected this for URIs where a value in the query string part is '*'. Up to version 2.19 of the jersey-common library, there is no encoding happening, starting with 2.20 it gets encoded.
Is this a bug or a bugfix or just a switch between two valid results?
UPDATE
According to the bug report linked in peeskillet's comment they fixed a bug in order to adhere to the UriBuilder API.