--- src/sys/dev/raid/aac/aac_cam.c	2008/02/10 00:01:03	1.9
+++ src/sys/dev/raid/aac/aac_cam.c	2008/05/18 20:30:23	1.10
@@ -171,7 +171,7 @@ aac_cam_attach(device_t dev)
 		return (EIO);
 
 	sim = cam_sim_alloc(aac_cam_action, aac_cam_poll, "aacp", camsc,
-	    device_get_unit(dev), 1, 1, devq);
+	    device_get_unit(dev), &sim_mplock, 1, 1, devq);
 	cam_simq_release(devq);
 	if (sim == NULL) {
 		return (EIO);