So, I'm still trying to get a working version of gstreamer, compiled from source. This turned out to be its own little project, due to the huge number of dependencies.
Which arm toolchain should I use? The codesourcery one that I've seen recommended doesn't seem to be available anymore, and the package that replaced it has a glibc 2.18 (I think), whereas the AR.Drone has glibc 2.11.
How does paparazzi get around this? It seems to want to install libc6-dev-armel-cross, which has glibc 2.15. It it linked statically? This doesn't seem to be an option for gstreamer. Too many dependencies.