opendkim currently doesn't properly work with UTF-8 in domain names. There's an upstream bugreport with a patch from the maintainer of zdkimfilter [1]. Unfortunately the project seems rather inactive/unmaintained and the patch doesn't apply to the version we currently have in Gentoo. Not sure what the best course of action here is, maybe we should switch to the latest opendkim beta version and apply the utf8-patch on top. (I'd like to add a zdkimfilter package, but right now it causes test failures due to this issue.) [1] https://github.com/trusteddomainproject/OpenDKIM/issues/47
(In reply to Hanno Böck from comment #0) > opendkim currently doesn't properly work with UTF-8 in domain names. That's not exactly a common scenario, so I see no reason to rush it. I may look into this in a few weeks, after the Gentoo recruiters process my application.
Given the inactivity upstream, I won't spend time on this issue. Perhaps somebody else wants to address this, though.
Realistically we can't fix this. We would have to fork OpenDKIM and start merging some of the outstanding patches to bring sanity to the set, and I don't think any of us have time to adopt a full-grown project.