diff --git a/example/passmass b/example/passmass
index ef029aa..7b67352 100755
--- a/example/passmass
+++ b/example/passmass
@@ -178,7 +178,7 @@ for {set i 0} {$i<$argc} {incr i} {
     }
 
     if ($su) {
-	send "su -\r"
+	send "/bin/su -\r"
 	expect -nocase "password:"
 	send "$password(old)\r"
 	expect "# "