I was packaging geany-plugins SCM in my Gentoo overlay for a while now and I recently tried to migrate to Exherbo. I then had to package it for Exherbo too.
Even with my Gentoo ebuilds, I had to hack a little to fix a typo in the GeanyPG Makefile.am, I didn't bugreport, it was trivial, and somebody would notice it upstream.
Then as my Exherbo doesn't have yet GPGME, it highlighted that the AM_PATH_GPGME macro is actually provided by GPGME.
The attached patch fixes these two little issues. It checks if the AM_PATH_GPGME macro is defined if we want the GPG support.
The big part for Exherbo is that geany-plugins try to install empty directories. The point is that disabling a plugin would install its docs, but I don't have any doc installed for these ones. It definitely sound like a bug to me.
I think it's trivial to fix it, either by adding docs to install or remove the install action.