diff --git a/sys/dev/acpi/aiboost.c b/sys/dev/acpi/aiboost.c
index eef4a50cc29d..e1da41e3634f 100644
--- a/sys/dev/acpi/aiboost.c
+++ b/sys/dev/acpi/aiboost.c
@@ -1,4 +1,4 @@
-/* $NetBSD: aiboost.c,v 1.7 2007/07/01 20:45:10 xtraeme Exp $ */
+/* $NetBSD: aiboost.c,v 1.8 2007/07/02 10:06:58 xtraeme Exp $ */
 
 /*-
  * Copyright (c) 2007 Juan Romero Pardines
@@ -28,7 +28,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: aiboost.c,v 1.7 2007/07/01 20:45:10 xtraeme Exp $");
+__KERNEL_RCSID(0, "$NetBSD: aiboost.c,v 1.8 2007/07/02 10:06:58 xtraeme Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -211,26 +211,32 @@ aiboost_refresh_sensors(struct aiboost_softc *sc, envsys_data_t *edata)
 	case ENVSYS_STEMP:
 		/* Temperatures */
 		val = aiboost_get_value(h, "RTMP", sc->sc_aitemp->elem[i].id);
+		if (val == -1)
+			edata->state = ENVSYS_SINVALID;
 		/* envsys(9) wants mK... convert from Celsius. */
-		sc->sc_data[i].value_cur = val * 100000 + 273150000;
+		edata->value_cur = val * 100000 + 273150000;
 		DPRINTF(("%s: temp[%d] value_cur=%d val=%d j=%d\n", __func__,
-		    i, sc->sc_data[i].value_cur, val, j));
+		    i, edata->value_cur, val, j));
 		break;
 	case ENVSYS_SVOLTS_DC:
 		/* Voltages */
 		j = i - sc->sc_aitemp->num;
 		val = aiboost_get_value(h, "RVLT", sc->sc_aivolt->elem[j].id);
+		if (val == -1)
+			edata->state = ENVSYS_SINVALID;
 		/* envsys(4) wants mV... */
-		sc->sc_data[i].value_cur = val * 10000;
-		sc->sc_data[i].value_cur /= 10;
+		edata->value_cur = val * 10000;
+		edata->value_cur /= 10;
 		DPRINTF(("%s: volt[%d] value_cur=%d val=%d j=%d\n", __func__,
-		    i, sc->sc_data[i].value_cur, val, j));
+		    i, edata->value_cur, val, j));
 		break;
 	case ENVSYS_SFANRPM:
 		/* Fans */
 		j = i - (sc->sc_aitemp->num + sc->sc_aivolt->num);
 		val = aiboost_get_value(h, "RFAN", sc->sc_aifan->elem[j].id);
-		sc->sc_data[i].value_cur = val;
+		if (val == -1)
+			edata->state = ENVSYS_SINVALID;
+		edata->value_cur = val;
 		DPRINTF(("%s: fan[%d] val=%d j=%d\n", __func__, i, val, j));
 		break;
 	}