[Netarchivesuite-users] CRAWL ENDING - Finished - Ended by operator

[aponb at gmx.at]

A configuration, which will be started every four hours, brings 
sometimes in the crawler log the message
"CRAWL ENDING - Finished - Ended by operator"
instead of only
"CRAWL ENDING - Finished"

and in fact in these jobs, there are some pages missing, which should 
have been crawled.

Do you know what's the reason for that behavior?