diff --git a/Foundation/include/Poco/DateTime.h b/Foundation/include/Poco/DateTime.h
index a50577031..5357a4ee3 100644
--- a/Foundation/include/Poco/DateTime.h
+++ b/Foundation/include/Poco/DateTime.h
@@ -427,6 +427,16 @@ inline void swap(DateTime& d1, DateTime& d2)
 }
 
 
+inline void DateTime::checkLimit(short& lower, short& higher, short limit)
+{
+	if (lower >= limit)
+	{
+		higher += short(lower / limit);
+		lower = short(lower % limit);
+	}
+}
+
+
 } // namespace Poco
 
 
diff --git a/Foundation/src/DateTime.cpp b/Foundation/src/DateTime.cpp
index 884d3f8c2..b5bc9e3e3 100644
--- a/Foundation/src/DateTime.cpp
+++ b/Foundation/src/DateTime.cpp
@@ -335,23 +335,13 @@ double DateTime::toJulianDay(int year, int month, int day, int hour, int minute,
 }
 
 
-void DateTime::checkLimit(short& lower, short& higher, short limit)
-{
-	if (lower > limit)
-	{
-		higher += short(lower / limit);
-		lower   = short((lower % limit) - 1);
-	}
-}
-
-
 void DateTime::normalize()
 {
-	checkLimit(_microsecond, _millisecond, 999);
-	checkLimit(_millisecond, _second, 999);
-	checkLimit(_second, _minute, 59);
-	checkLimit(_minute, _hour, 59);
-	checkLimit(_hour, _day, 23);
+	checkLimit(_microsecond, _millisecond, 1000);
+	checkLimit(_millisecond, _second, 1000);
+	checkLimit(_second, _minute, 60);
+	checkLimit(_minute, _hour, 60);
+	checkLimit(_hour, _day, 24);
 
 	if (_day > daysOfMonth(_year, _month))
 	{