Vault: http://dev.bukkit.org/server-mods/vault/
Note: for proper faction bank support in iCo5 and EssentialsEco, I recommend waiting for Vault 1.2.5 to be released which addresses faction account creation issues.
"logFactionCreate": true, - log faction creation
"logFactionDisband": true, - log factions being disbanded, by command or by circumstance
"logFactionJoin": true, - log player joining a faction
"logFactionKick": true, - log player being kicked from a faction
"logFactionLeave": true, - log player leaving a faction
"logLandClaims": true, - log land being claimed (including safe zone and war zone)
"logLandUnclaims": true, - log land being unclaimed (including safe zone and war zone)
"logMoneyTransactions": true, - log money being deposited, withdrawn, and otherwise transferred in relation to faction banks
Also a fix for a potential NPE from players logging out and Spout appearance handler referencing them afterwards