Notes R4 allows you to set a database's properties so that ACL's are consistent across all replicas.
Notes R5 has built in tools for updating the ACL's across multiple databases.
Percussion Software has a product called Server Admin Plus that will also let you manage and audit ACL information.
Candle also has a system administration tool.
IVES Technologies has a product called ACL Reporter Updater which is a platform independent administration tool that provides security management for enterprise-wide Lotus Notes/Domino networks.