--- 800.scrub-zfs.orig	2011-06-30 22:52:01.291279403 -0700
+++ 800.scrub-zfs	2011-06-30 22:52:08.707039940 -0700
@@ -51,10 +51,11 @@
 			_pool_threshold=${daily_scrub_zfs_default_threshold}
 		fi
 
-		_last_scrub=$(zpool history ${pool} | \
-		    egrep "^[0-9\.\:\-]{19} zpool scrub ${pool}\$" | tail -1 |\
-		    cut -d ' ' -f 1)
-		if [ -z "${_last_scrub}" ]; then
+        _last_successful_scrub=$(zpool history ${pool} | \
+            egrep "^[0-9\.\:\-]{19} zpool scrub( -s | )${pool}\$" |  \
+            awk 'BEGIN { scrub1="" }; /zpool scrub -s/{ scrub1=scrub2 }; \
+                /zpool scrub/ && ! / -s /{ scrub2=scrub1; scrub1=$1 }; END { print scrub1 }')
+		if [ -z "${_last_successful_scrub}" ]; then
 			# creation time of the pool if no scrub was done
 			_last_scrub=$(zpool history ${pool} | \
 			    sed -ne '2s/ .*$//p')