--- /etc/cron.d/mdadm.orig	2011-09-11 14:48:56.000000000 +0400
+++ /etc/cron.d/mdadm	2011-12-17 18:00:33.000000000 +0400
@@ -5,8 +5,7 @@
 # distributed under the terms of the Artistic Licence 2.0
 #
 
-# By default, run at 00:57 on every Sunday, but do nothing unless the day of
-# the month is less than or equal to 7. Thus, only run on the first Sunday of
-# each month. crontab(5) sucks, unfortunately, in this regard; therefore this
-# hack (see #380425).
-57 0 * * 0 root if [ -x /usr/share/mdadm/checkarray ] && [ $(date +\%d) -le 7 ]; then /usr/share/mdadm/checkarray --cron --all --idle --quiet; fi
+# By default, start (or continue unfinished checks) at 00:57
+# on every Sunday and stop (interrupt) checks at 04:57.
+57 0 * * 0 root [ -x /usr/share/mdadm/checkarray ] && /usr/share/mdadm/checkarray --cron --all --quiet
+57 4 * * 0 root [ -x /usr/share/mdadm/checkarray ] && /usr/share/mdadm/checkarray --cron --all --quiet --cancel