diff --git a/src/lib/svc/method/zfs-auto-snapshot b/src/lib/svc/method/zfs-auto-snapshot
index 6c1e566..2e5a932 100644
--- a/src/lib/svc/method/zfs-auto-snapshot
+++ b/src/lib/svc/method/zfs-auto-snapshot
@@ -1,4 +1,4 @@
-#!/usr/bin/ksh
+#!/usr/bin/ksh93
 
 #
 # CDDL HEADER START