Hm, don't you mean the other way around?
Pike v7.7 release 87 running Hilfe v3.5 (Incremental Pike Frontend)
Standards.URI("http://www.roxen.com/%22)-%3Equote(%22r%C3%A4ksm%C3%B6rg%C3%A5s");
(1) Result: "r\344ksm\366rg\345s"
Standards.URI("http://www.roxen.com/%22)-%3Ehttp_encode(%22r%C3%A4ksm%C3%B6rg%C3%A5s");
(2) Result: "r%e4ksm%f6rg%e5s"