I just installed Exim 4.73 on Ubuntu using apt-get. I was able to easily integrate DKIM signing because of it's integration with Exim. I'm having some trouble with DomainKeys support. Most of the online documentation recommends compiling Exim with the DomainKeys library which I'd rather not do. Is there an easier way to have my Exim installation sign outgoing messages with a DomainKey signature? I noticed a package called dk-filter but couldn't find much documentation about it online. Thanks in advance.
There is no "one button way" of doing that. Experimental with lib or you can use DKIMproxy that works with DKIM and DomainKeys to sign outgoing mail.