Summary pretty much sums it up, the makefile sets $DESTDIR as / since it's undefined, so it always installs in / instead of /usr. Since Portage and other PM's don't honor or use $DESTDIR, and this package does not use autotools in any way what so ever. The only other solution is to provide a diff. Diff's will be attached.
Created attachment 146813 [details, diff] one large diff to patch the ebuild/etc...
Created attachment 146815 [details, diff] dhcdbd-3.0-location.patch Patch that patches the source, uses epatch to patch it.
Created attachment 146820 [details, diff] patch patch to modify the init.d defined in the portage repo, to notice the new location.
Note, I won't provide a patch for the ebuild since that is trivial. Just add epatch ${FILESDIR}/${PN}-3.0-location.patch
Hi Scott, my apologies for never getting around to this. The package was masked last night for removal as it's been obsoleted by NetworkManager 0.7.0 so I'm going to mark this as won't fix. I do appreciate that you took the time to write this up.