[syslog-ng] syslog-ng 2.0.0 and "-- MARK --" messages

Hello! I'm wondering about the MARK messages that show up in my logs. While I have deduced that the default value is 1200 seconds, I can't seem to turn it off. Adding a "mark(86400);" stanza gets me a syntax error that the mark() keyword isn't valid. Am I missing something very basic here, or is there more to this? Thank you in advance. -- A: Because it's counterintuitive to the way we read. Q: Why is top-posting bad?