@orangy: My UriBuilder dealt with this in a blunt way: have two ways of accessing these parameters, one has multimap, the other does not. My UriBuilder keeps them in sync. Not the best, but is one answer. Also note that Java Url Encoding isn't correct for all parts of URL's, this dir contains updated encoders and the builder: https://github.com/klutter/klutter/tree/master/core-jdk6/src/main/kotlin/uy/klutter/core/uri