My Adium chat logs were not being indexed by Spotlight under Leopard. I went inside the Adium package, in /Applications/Adium/Contents/Library/Spotlight, double-clicked the AdiumSpotlightImporter… and it didn’t change anything. Still no result.
What to do? Keep looking.
Update: It gets weirder. The mdfind utility actually finds the chat logs I’m looking for, but they don’t appear as results in the Spotlight menu or window. Every item is enabled in the Spotlight pref pane. If I move a chat log out of the ~/Library/Application Support/Adium 2.0/bla bla bla/logs folder, e.g. on the Desktop, Spotlight finds it. Somehow the Spotlight menu decides not to return results from within ~/Library…
Update 2: Argh. In order for Spotlight to return results from within ~/Library, you have to specify that you want to see results from “System Files”. Of course, items such as emails from Apple Mail are not considered as “System Files”, only third-party application files. Bad, bad move.