diff --git a/panel-plugin/eyes.c b/panel-plugin/eyes.c
index baa278d..beb88fd 100644
--- a/panel-plugin/eyes.c
+++ b/panel-plugin/eyes.c
@@ -161,9 +161,10 @@ draw_eye (EyesPlugin *eyes,
 
 
 
-static gint
-timer_cb (EyesPlugin *eyes)
+static gboolean
+timer_cb (gpointer user_data)
 {
+    EyesPlugin *eyes = user_data;
     gint x, y;
     gint pupil_x, pupil_y;
     gint i;
@@ -291,8 +292,7 @@ eyes_applet_fill (EyesPlugin *eyes)
 
     if (eyes->timeout_id == 0)
     {
-        eyes->timeout_id = g_timeout_add (UPDATE_TIMEOUT,
-                                         (GSourceFunc) timer_cb, eyes);
+        eyes->timeout_id = g_timeout_add (UPDATE_TIMEOUT, timer_cb, eyes);
     }
 
     return TRUE;