diff --git a/src/share/classes/java/util/Calendar.java b/src/share/classes/java/util/Calendar.java
index e1f65e6a88500b6177351229844bc19a682f8927..7fa8296433c00011aaca10e5c676a9fcf82eb0e2 100644
--- a/src/share/classes/java/util/Calendar.java
+++ b/src/share/classes/java/util/Calendar.java
@@ -1190,7 +1190,9 @@ public abstract class Calendar implements Serializable, Cloneable, Comparable<Ca
      */
     public void set(int field, int value)
     {
-        if (isLenient() && areFieldsSet && !areAllFieldsSet) {
+        // If the fields are partially normalized, calculate all the
+        // fields before changing any fields.
+        if (areFieldsSet && !areAllFieldsSet) {
             computeFields();
         }
         internalSet(field, value);
diff --git a/test/java/util/Calendar/Bug6645263.java b/test/java/util/Calendar/Bug6645263.java
new file mode 100644
index 0000000000000000000000000000000000000000..148926e621035448118d1556a6c77cc23b17840d
--- /dev/null
+++ b/test/java/util/Calendar/Bug6645263.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2007 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+/*
+ * @test
+ * @bug 6645263
+ * @summary Test field normalization in non-lenient from the partially normalized state
+ */
+
+import java.util.*;
+
+public class Bug6645263 {
+    public static void main(String[] args) {
+        Calendar cal = new GregorianCalendar(Locale.US);
+        cal.setLenient(false);
+        cal.set(Calendar.YEAR, 2007);
+        cal.set(Calendar.MONTH, Calendar.NOVEMBER);
+        cal.set(Calendar.WEEK_OF_MONTH, 4);
+        cal.set(Calendar.DAY_OF_WEEK, 1);
+        // Let cal calculate the time from the given fields
+        cal.getTime();
+
+        // Change DAY_OF_MONTH
+        cal.set(Calendar.DAY_OF_MONTH, 1);
+        // The following line shouldn't throw an IllegalArgumentException.
+        cal.getTime();
+   }
+}