binlog-do-db or binlog-ignore-db are in effect.   (In the future 5.1? 5.0? I think 
each statement should be verified against the filtering criteria based on the database
it *uses* and not the *current* one.  But, right now the *current* database is what 
counts according to the semantics of the manual.)


sql/log.cc:
  BUG#6749: If there is no current database, then nothing should be binlogged if
  binlog-do-db or binlog-ignore-db are in effect.   (In the future I think that each 
  statement should be verified against the filtering criteria based on the database
  it *uses* and not the *current* one.  But, right now the *current* database is what 
  counts according to the semantics of the manual.)