Created attachment 269225 [details, diff] Makefile patch to add missing dependencies. Bug 8236 lives again. If I had to guess, I'd say that the fix back then was to add MAKEOPTS="-j1" to the ebuild. Now that we've removed that, the build can fail again. The root cause is an unlisted dependency on uint32.h. The attached patch adds them in the proper places. It turns out this is the same patch proposed way back in 2002, only with the line numbers updated.
To be explicit: this need only be applied when USE=ipv6. The ipv6 patch is what breaks the Makefile.
Fixed in -r24. + 11 Apr 2011; Dane Smith <c1pher@gentoo.org> djbdns-1.05-r24.ebuild, + +files/makefile-parallel.patch: + Add patch to fix parallel make issues when USE="ipv6" wrt bug 362771. + Thanks + Michael for spotting and fixing this. +