diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/calendars/entities/BaseCalendar.java b/navalplanner-business/src/main/java/org/navalplanner/business/calendars/entities/BaseCalendar.java
index 3e7adc950..42812896d 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/calendars/entities/BaseCalendar.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/calendars/entities/BaseCalendar.java
@@ -194,6 +194,11 @@ public class BaseCalendar extends BaseEntity implements IValidable {
 
     public void addExceptionDay(ExceptionDay day)
             throws IllegalArgumentException {
+        if (day.getDate().compareTo(new LocalDate()) <= 0) {
+            throw new IllegalArgumentException(
+                    "You can not modify the past adding a new exception day");
+        }
+
         if (shouldUsePreviousCalendar(day.getDate())) {
             previousCalendar.addExceptionDay(day);
         } else if (shouldUseNextCalendar(day.getDate())) {
@@ -214,6 +219,11 @@ public class BaseCalendar extends BaseEntity implements IValidable {
 
     public void removeExceptionDay(LocalDate date)
             throws IllegalArgumentException {
+        if (date.compareTo(new LocalDate()) <= 0) {
+            throw new IllegalArgumentException(
+                    "You can not modify the past removing an exception day");
+        }
+
         if (shouldUsePreviousCalendar(date)) {
             previousCalendar.removeExceptionDay(date);
         } else if (shouldUseNextCalendar(date)) {
diff --git a/navalplanner-business/src/test/java/org/navalplanner/business/test/calendars/entities/BaseCalendarTest.java b/navalplanner-business/src/test/java/org/navalplanner/business/test/calendars/entities/BaseCalendarTest.java
index 2ae243f5a..bc529c531 100644
--- a/navalplanner-business/src/test/java/org/navalplanner/business/test/calendars/entities/BaseCalendarTest.java
+++ b/navalplanner-business/src/test/java/org/navalplanner/business/test/calendars/entities/BaseCalendarTest.java
@@ -22,17 +22,24 @@ import org.navalplanner.business.common.exceptions.ValidationException;
  */
 public class BaseCalendarTest {
 
-    public static final LocalDate MONDAY_LOCAL_DATE = new LocalDate(2009, 8, 10);
-    public static final LocalDate TUESDAY_LOCAL_DATE = new LocalDate(2009, 8,
-            11);
-    public static final LocalDate WEDNESDAY_LOCAL_DATE = new LocalDate(2009, 8,
-            12);
-    public static final LocalDate THURSDAY_LOCAL_DATE = new LocalDate(2009, 8,
-            13);
-    public static final LocalDate FRIDAY_LOCAL_DATE = new LocalDate(2009, 8, 14);
-    public static final LocalDate SATURDAY_LOCAL_DATE = new LocalDate(2009, 8,
-            15);
-    public static final LocalDate SUNDAY_LOCAL_DATE = new LocalDate(2009, 8, 16);
+    public static final LocalDate JUNE_NEXT_YEAR = new LocalDate(
+            (new LocalDate())
+            .getYear(), 6, 1).plusYears(1);
+
+    public static final LocalDate MONDAY_LOCAL_DATE = JUNE_NEXT_YEAR
+            .dayOfWeek().withMinimumValue();
+    public static final LocalDate TUESDAY_LOCAL_DATE = MONDAY_LOCAL_DATE
+            .plusDays(1);
+    public static final LocalDate WEDNESDAY_LOCAL_DATE = MONDAY_LOCAL_DATE
+            .plusDays(2);
+    public static final LocalDate THURSDAY_LOCAL_DATE = MONDAY_LOCAL_DATE
+            .plusDays(3);
+    public static final LocalDate FRIDAY_LOCAL_DATE = MONDAY_LOCAL_DATE
+            .plusDays(4);
+    public static final LocalDate SATURDAY_LOCAL_DATE = MONDAY_LOCAL_DATE
+            .plusDays(5);
+    public static final LocalDate SUNDAY_LOCAL_DATE = MONDAY_LOCAL_DATE
+            .plusDays(6);
 
     private static final LocalDate[] DAYS_OF_A_WEEK_EXAMPLE = {
             MONDAY_LOCAL_DATE, TUESDAY_LOCAL_DATE, WEDNESDAY_LOCAL_DATE,
@@ -40,7 +47,7 @@ public class BaseCalendarTest {
             SUNDAY_LOCAL_DATE };
 
     public static final LocalDate CHRISTMAS_DAY_LOCAL_DATE = new LocalDate(
-            2009, 12, 25);
+            JUNE_NEXT_YEAR.getYear(), 12, 25);
 
     public static BaseCalendar createBasicCalendar() {
         BaseCalendar calendar = BaseCalendar.create();
@@ -602,4 +609,23 @@ public class BaseCalendarTest {
                 equalTo(lastVersion));
     }
 
+    @Test(expected = IllegalArgumentException.class)
+    public void testNotAllowCreateExceptionsInThePast() {
+        BaseCalendar calendar = createBasicCalendar();
+
+        LocalDate pastMonth = (new LocalDate()).minusMonths(1);
+        ExceptionDay exceptionDay = ExceptionDay.create(pastMonth, 0);
+
+        calendar.addExceptionDay(exceptionDay);
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testNotAllowRemoveExceptionsInThePast() {
+        BaseCalendar calendar = createBasicCalendar();
+
+        LocalDate pastMonth = (new LocalDate()).minusMonths(1);
+
+        calendar.removeExceptionDay(pastMonth);
+    }
+
 }