At the November MySQL User Group, Patrick Galbraith ran into a problem where binlog-do-db was duplicated. It manifests itself like this: (copied from http://lists.mysql.com/replication/607)
master my.cnf: binlog-do-db=db1
slave my.cnf: replicate-do-db=db1;
Relevant show slave status output
Replicate_Do_DB: db1;,db1;
When db1 is modified on master, Read_Master_Log_Pos and Relay_Log_Pos do changes, also I can open and see the changes in rh3-relay-bin.000002, but they do not appear in [...]