diff --git a/libraries/TinyPower/TinyPower.h b/libraries/TinyPower/TinyPower.h
index 134947a..2d834d3 100644
--- a/libraries/TinyPower/TinyPower.h
+++ b/libraries/TinyPower/TinyPower.h
@@ -36,16 +36,19 @@ public:
 	  sei();                                  // Enable interrupts
 	}
 
-	static void enableWdt(byte time)
-	{
-	    MCUSR = 0x00;
-	    WDTCR |= _BV(WDCE) | _BV(WDE);
-	    WDTCR = _BV(WDIE) | time;
+	static void enableWdt(byte time) {
+		cli();
+		MCUSR = 0x00;
+		WDTCR |= _BV(WDCE) | _BV(WDE);
+		WDTCR = _BV(WDIE) | (time & 0x08 ? _WD_PS3_MASK : 0x00) | (time & 0x07);
+		sei();
 	}
 
 	static void disableWdt() {
-	  MCUSR = 0x00;
-	  WDTCR |= _BV(WDCE) | _BV(WDE);
-	  WDTCR = 0x00;
+		cli();
+		MCUSR = 0x00;
+		WDTCR |= _BV(WDCE) | _BV(WDE);
+		WDTCR = 0x00;
+		sei();
 	}
 };