[LAU] Where should lv2core put lv2.h?

I installed lv2core a couple of months ago on a Slackware 13.1 system, and I created my own SlackBuild script to compile and install it, which configured waf with "--prefix=/usr --configdir=/etc --libdir=/usr/lib64 --mandir=/usr/man". This put a copy of lv2.h in /usr/include/, and another copy in /usr/lib64/lv2/lv2core.lv2/. I also installed SLV2 with no problems. Since lilv came out (along with a couple of other packages to replace SLV2), I decided to install it. I installed serd and sord first, but when I try to compile lilv, it bombs out because it can't find lv2/lv2plug.in/ns/lv2core/lv2.h (presumably, this path would be appended to /usr/include/ for the complete path), and I can't figure out any way to get lv2.h there without just creating each directory in the path myself and copying it there. There is no mention of that path anywhere in the waf scripts. The only mention I can find of that path is in the README and INSTALL files, both of which suggest that programmers use that path in their build scripts to determine whether lv2core is installed. Why is that being recommended when the lv2core scripts don't install it there? Am I missing something? This is driving me crazy. Any help in preserving my sanity would be greatly appreciated. Chuck P.S. I've already tried putting this in my SlackBuild script: sed -i -e "s,lv2/lv2plug.in/ns/lv2core/,," wscript lilv/lilv.h and that allows it to compile and install alright, but it means I'll also have to do something similar to every other program that looks for lv2.h in that location, and that doesn't seem to be a be a very nice solution.