Flume spans log file with "Spooling Directory Source runner has shutdown" messages at INFO level

When I start an agent with the following config, the spooling directory source emits "14/05/14 22:36:12 INFO source.SpoolDirectorySource: Spooling Directory Source runner has shutdown." messages twice a second. Pretty innocuous but it will fill up the file system needlessly and get in the way of other INFO messages.

cis.sources = httpd
cis.sinks = loggerSink
cis.channels = mem2logger

cis.sources.httpd.type = spooldir
cis.sources.httpd.spoolDir = /var/log/httpd
cis.sources.httpd.trackerDir = /var/lib/flume-ng/tracker/httpd
cis.sources.httpd.channels = mem2logger

cis.sinks.loggerSink.type = logger
cis.sinks.loggerSink.channel = mem2logger

cis.channels.mem2logger.type = memory
cis.channels.mem2logger.capacity = 10000
cis.channels.mem2logger.transactionCapacity = 1000