Preliminary investigations of mitch's gimp-plugin-template today, which resulted in some light dancing with autoconf. But more importantly, there are (unofficial) i386 Debian packages of GIMP 1.1.23 at http://yakk.ucc.asn.au/gimp/ (for aussies) and

deb http://download.sourceforge.net/gimp-plug-ins/ ./

for the right-side-up half of the world.

Many thanks to yakk for doing this while gimp's regular debian maintainer is swamped by his academic life.