diff --git a/src/PantheonGreeter.vala b/src/PantheonGreeter.vala
index 11aa4c0..ae7bf7e 100644
--- a/src/PantheonGreeter.vala
+++ b/src/PantheonGreeter.vala
@@ -163,7 +163,7 @@ public class PantheonGreeter : Gtk.Window {
             warning (e.message);
         }
         if (activate_numlock) {
-            Granite.Services.System.execute_command ("/usr/bin/numlockx on");
+            Granite.Services.System.execute_command ("@numlockx@/bin/numlockx on");
         }
 
         var screensaver_timeout = 60;