I changed the version of my hacked libpurple0 so it is lower than the pidgin one, I ditched the pidgin-data dependency (thanks qwerty12) and I put it back in my repository as version 2.5.0.qole -- I did a fresh install and updated my instructions. It's a lot less work this time and (perhaps because I didn't have the Chinook repositories?) the link local seems to be working without hacks.