diff --git a/mailman/cron/crontab.in.in b/mailman/cron/crontab.in.in
index 49f27c7..34df575 100755
--- a/mailman/cron/crontab.in.in
+++ b/mailman/cron/crontab.in.in
@@ -1,24 +1,24 @@
 # At 8AM every day, mail reminders to admins as to pending requests.
 # They are less likely to ignore these reminders if they're mailed
 # early in the morning, but of course, this is local time... ;)
-0 8 * * * @PYTHON@ -S @prefix@/cron/checkdbs
+0 8 * * * mailman [ -f @LOCKFILE@ ] && @PYTHON@ -S @prefix@/cron/checkdbs
 #
 # At 9AM, send notifications to disabled members that are due to be
 # reminded to re-enable their accounts.
-0 9 * * * @PYTHON@ -S @prefix@/cron/disabled
+0 9 * * * mailman [ -f @LOCKFILE@ ] && @PYTHON@ -S @prefix@/cron/disabled
 #
 # Noon, mail digests for lists that do periodic as well as threshhold delivery.
-0 12 * * * @PYTHON@ -S @prefix@/cron/senddigests
+0 12 * * * mailman [ -f @LOCKFILE@ ] && @PYTHON@ -S @prefix@/cron/senddigests
 #
 # 5 AM on the first of each month, mail out password reminders.
-0 5 1 * * @PYTHON@ -S @prefix@/cron/mailpasswds
+0 5 1 * * mailman [ -f @LOCKFILE@ ] && @PYTHON@ -S @prefix@/cron/mailpasswds
 #
 # Every 5 mins, try to gate news to mail.  You can comment this one out
 # if you don't want to allow gating, or don't have any going on right now,
 # or want to exclusively use a callback strategy instead of polling.
-0,5,10,15,20,25,30,35,40,45,50,55 * * * * @PYTHON@ -S @prefix@/cron/gate_news
+*/5 * * * * mailman [ -f @LOCKFILE@ ] && @PYTHON@ -S @prefix@/cron/gate_news
 #
 # At 3:27am every night, regenerate the gzip'd archive file.  Only
 # turn this on if the internal archiver is used and
 # GZIP_ARCHIVE_TXT_FILES is false in mm_cfg.py
-27 3 * * * @PYTHON@ -S @prefix@/cron/nightly_gzip
+27 3 * * * mailman [ -f @LOCKFILE@ ] && @PYTHON@ -S @prefix@/cron/nightly_gzip