diff --git a/navalplanner-business/src/test/java/org/navalplanner/business/test/calendars/daos/BaseCalendarDAOTest.java b/navalplanner-business/src/test/java/org/navalplanner/business/test/calendars/daos/BaseCalendarDAOTest.java
new file mode 100644
index 000000000..d055838ad
--- /dev/null
+++ b/navalplanner-business/src/test/java/org/navalplanner/business/test/calendars/daos/BaseCalendarDAOTest.java
@@ -0,0 +1,59 @@
+package org.navalplanner.business.test.calendars.daos;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.navalplanner.business.BusinessGlobalNames.BUSINESS_SPRING_CONFIG_FILE;
+import static org.navalplanner.business.test.BusinessGlobalNames.BUSINESS_SPRING_CONFIG_TEST_FILE;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.navalplanner.business.calendars.daos.BaseCalendarDAO;
+import org.navalplanner.business.calendars.daos.IBaseCalendarDAO;
+import org.navalplanner.business.calendars.entities.BaseCalendar;
+import org.navalplanner.business.common.exceptions.InstanceNotFoundException;
+import org.navalplanner.business.test.calendars.entities.BaseCalendarTest;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.transaction.annotation.Transactional;
+
+/**
+ * Tests for {@link BaseCalendarDAO}
+ *
+ * @author Manuel Rego Casasnovas <mrego@igalia.com>
+ */
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(locations = { BUSINESS_SPRING_CONFIG_FILE,
+        BUSINESS_SPRING_CONFIG_TEST_FILE })
+@Transactional
+public class BaseCalendarDAOTest {
+
+    @Autowired
+    IBaseCalendarDAO baseCalendarDAO;
+
+    @Test
+    public void saveBasicCalendar() {
+        BaseCalendar calendar = BaseCalendarTest.createBasicCalendar();
+        baseCalendarDAO.save(calendar);
+        assertTrue(baseCalendarDAO.exists(calendar.getId()));
+    }
+
+    @Test
+    public void saveBasicCalendarWithExceptionDay() {
+        BaseCalendar calendar = BaseCalendarTest.createBasicCalendar();
+        BaseCalendarTest.addChristmasAsExceptionDay(calendar);
+
+        baseCalendarDAO.save(calendar);
+        assertTrue(baseCalendarDAO.exists(calendar.getId()));
+
+        try {
+            BaseCalendar savedCalendar = baseCalendarDAO.find(calendar.getId());
+            assertThat(savedCalendar.getExceptions().size(), equalTo(1));
+        } catch (InstanceNotFoundException e) {
+            fail("It should not throw an exception");
+        }
+    }
+
+}
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
new file mode 100644
index 000000000..7106792f4
--- /dev/null
+++ b/navalplanner-business/src/test/java/org/navalplanner/business/test/calendars/entities/BaseCalendarTest.java
@@ -0,0 +1,382 @@
+package org.navalplanner.business.test.calendars.entities;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.fail;
+
+import org.joda.time.LocalDate;
+import org.junit.Test;
+import org.navalplanner.business.calendars.entities.BaseCalendar;
+import org.navalplanner.business.calendars.entities.ExceptionDay;
+import org.navalplanner.business.common.exceptions.ValidationException;
+
+/**
+ * Tests for {@link BaseCalendar}.
+ *
+ * @author Manuel Rego Casasnovas <mrego@igalia.com>
+ */
+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 CHRISTMAS_DAY_LOCAL_DATE = new LocalDate(2009, 12,
+            25);
+
+    public static BaseCalendar createBasicCalendar() {
+        BaseCalendar calendar = BaseCalendar.create();
+
+        calendar.setName("Test");
+
+        calendar.setMonday(8);
+        calendar.setTuesday(8);
+        calendar.setWednesday(8);
+        calendar.setThursday(8);
+        calendar.setFriday(8);
+        calendar.setSaturday(0);
+        calendar.setSunday(0);
+
+        return calendar;
+    }
+
+    public static void addChristmasAsExceptionDay(BaseCalendar calendar) {
+        ExceptionDay christmasDay = ExceptionDay.create(CHRISTMAS_DAY_LOCAL_DATE, 0);
+
+        calendar.addExceptionDay(christmasDay);
+    }
+
+    public static BaseCalendar createChristmasCalendar() {
+        BaseCalendar calendar = createBasicCalendar();
+        addChristmasAsExceptionDay(calendar);
+        return calendar;
+    }
+
+    @Test
+    public void testValidCalendar() {
+        BaseCalendar calendar = createBasicCalendar();
+        try {
+            calendar.checkValid();
+        } catch (ValidationException e) {
+            fail("It should not throw an exception");
+        }
+    }
+
+    @Test(expected = ValidationException.class)
+    public void testInvalidCalendar() throws ValidationException {
+        BaseCalendar calendar = new BaseCalendar();
+        calendar.checkValid();
+    }
+
+    @Test
+    public void testGetWorkableHoursBasic() {
+        BaseCalendar calendar = createBasicCalendar();
+
+        int wednesdayHours = calendar.getWorkableHours(WEDNESDAY_LOCAL_DATE);
+        assertThat(wednesdayHours, equalTo(8));
+
+        int sundayHours = calendar.getWorkableHours(SUNDAY_LOCAL_DATE);
+        assertThat(sundayHours, equalTo(0));
+    }
+
+    @Test
+    public void testGetWorkableHoursChristmas() {
+        BaseCalendar calendar = createChristmasCalendar();
+
+        int hours = calendar.getWorkableHours(CHRISTMAS_DAY_LOCAL_DATE);
+        assertThat(hours, equalTo(0));
+    }
+
+    @Test
+    public void testDeriveCalendar() {
+        BaseCalendar calendar = createBasicCalendar();
+        BaseCalendar derivedCalendar = calendar.newDerivedCalendar();
+
+        assertThat(derivedCalendar.getParent(), equalTo(calendar));
+    }
+
+    @Test
+    public void testGetWorkableHoursDerivedBasicCalendar() {
+        BaseCalendar calendar = createBasicCalendar().newDerivedCalendar();
+
+        int wednesdayHours = calendar.getWorkableHours(WEDNESDAY_LOCAL_DATE);
+        assertThat(wednesdayHours, equalTo(8));
+
+        int sundayHours = calendar.getWorkableHours(SUNDAY_LOCAL_DATE);
+        assertThat(sundayHours, equalTo(0));
+    }
+
+    @Test
+    public void testGetWorkableHoursDerivedChristmasCalendar() {
+        BaseCalendar calendar = createChristmasCalendar().newDerivedCalendar();
+
+        int hours = calendar.getWorkableHours(CHRISTMAS_DAY_LOCAL_DATE);
+        assertThat(hours, equalTo(0));
+    }
+
+    @Test
+    public void testGetWorkableHoursDerivedBasicCalendarWithException() {
+        BaseCalendar calendar = createBasicCalendar().newDerivedCalendar();
+
+        ExceptionDay day = ExceptionDay.create(WEDNESDAY_LOCAL_DATE, 4);
+        calendar.addExceptionDay(day);
+
+        int mondayHours = calendar.getWorkableHours(MONDAY_LOCAL_DATE);
+        assertThat(mondayHours, equalTo(8));
+
+        int wednesdayHours = calendar.getWorkableHours(WEDNESDAY_LOCAL_DATE);
+        assertThat(wednesdayHours, equalTo(4));
+
+        int sundayHours = calendar.getWorkableHours(SUNDAY_LOCAL_DATE);
+        assertThat(sundayHours, equalTo(0));
+    }
+
+    @Test
+    public void testGetWorkableHoursDerivedChristmasCalendarRedefiningExceptionDay() {
+        BaseCalendar calendar = createChristmasCalendar().newDerivedCalendar();
+
+        ExceptionDay day = ExceptionDay.create(CHRISTMAS_DAY_LOCAL_DATE, 4);
+        calendar.addExceptionDay(day);
+
+        int hours = calendar.getWorkableHours(CHRISTMAS_DAY_LOCAL_DATE);
+        assertThat(hours, equalTo(4));
+    }
+
+    @Test
+    public void testGettWorkableHoursInterval() {
+        BaseCalendar calendar = createBasicCalendar();
+
+        int mondayToWednesdayHours = calendar.getWorkableHours(MONDAY_LOCAL_DATE,
+                WEDNESDAY_LOCAL_DATE);
+        assertThat(mondayToWednesdayHours, equalTo(24));
+    }
+
+    @Test
+    public void testGettWorkableHoursPerWeek() {
+        BaseCalendar calendar = createBasicCalendar();
+
+        int weekHours = calendar.getWorkableHoursPerWeek(WEDNESDAY_LOCAL_DATE);
+        assertThat(weekHours, equalTo(40));
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testAddTwoExceptionDaysInTheSameDate() {
+        BaseCalendar calendar = createBasicCalendar();
+
+        ExceptionDay day = ExceptionDay.create(MONDAY_LOCAL_DATE, 8);
+        calendar.addExceptionDay(day);
+
+        ExceptionDay day2 = ExceptionDay.create(MONDAY_LOCAL_DATE, 4);
+        calendar.addExceptionDay(day2);
+    }
+
+    @Test
+    public void testCreateNewVersion() {
+        BaseCalendar calendar = createBasicCalendar();
+        BaseCalendar nextCalendar = calendar.newVersion();
+
+        assertThat(calendar, equalTo(nextCalendar.getPreviousCalendar()));
+        assertThat(nextCalendar, equalTo(calendar.getNextCalendar()));
+    }
+
+    @Test
+    public void testGettWorkableHoursNewVersion() {
+        BaseCalendar origCalendar = createBasicCalendar();
+        BaseCalendar newCalendar = origCalendar.newVersion(
+                MONDAY_LOCAL_DATE);
+
+        newCalendar.setWednesday(4);
+        newCalendar.setSunday(4);
+
+        int wednesdayHours = newCalendar
+                .getWorkableHours(WEDNESDAY_LOCAL_DATE);
+        assertThat(wednesdayHours, equalTo(4));
+        assertThat(wednesdayHours, equalTo(origCalendar
+                .getWorkableHours(WEDNESDAY_LOCAL_DATE)));
+
+        int wednesdayHoursPastWeek = newCalendar
+                .getWorkableHours(WEDNESDAY_LOCAL_DATE.minusWeeks(1));
+        assertThat(wednesdayHoursPastWeek, equalTo(8));
+        assertThat(wednesdayHoursPastWeek, equalTo(origCalendar
+                .getWorkableHours(WEDNESDAY_LOCAL_DATE.minusWeeks(1))));
+
+        int sundayHours = newCalendar.getWorkableHours(SUNDAY_LOCAL_DATE);
+        assertThat(sundayHours, equalTo(4));
+        assertThat(sundayHours, equalTo(origCalendar
+                .getWorkableHours(SUNDAY_LOCAL_DATE)));
+
+        int sundayHoursPastWeek = newCalendar
+                .getWorkableHours(SUNDAY_LOCAL_DATE
+                .minusWeeks(1));
+        assertThat(sundayHoursPastWeek, equalTo(0));
+        assertThat(sundayHoursPastWeek, equalTo(origCalendar
+                .getWorkableHours(SUNDAY_LOCAL_DATE.minusWeeks(1))));
+    }
+
+    @Test
+    public void testGettWorkableHoursNewVersionCheckingLimits() {
+        BaseCalendar origCalendar = createBasicCalendar();
+        BaseCalendar newCalendar = origCalendar.newVersion(
+                MONDAY_LOCAL_DATE);
+
+        newCalendar.setMonday(1);
+        newCalendar.setSunday(2);
+
+        int mondayHours = newCalendar.getWorkableHours(MONDAY_LOCAL_DATE);
+        assertThat(mondayHours, equalTo(1));
+        assertThat(mondayHours, equalTo(origCalendar
+                .getWorkableHours(MONDAY_LOCAL_DATE)));
+
+        int sundayHours = newCalendar.getWorkableHours(SUNDAY_LOCAL_DATE);
+        assertThat(sundayHours, equalTo(2));
+        assertThat(sundayHours, equalTo(origCalendar
+                .getWorkableHours(SUNDAY_LOCAL_DATE)));
+
+        int mondayHoursPastWeek = newCalendar.getWorkableHours(MONDAY_LOCAL_DATE
+                .minusWeeks(1));
+        assertThat(mondayHoursPastWeek, equalTo(8));
+        assertThat(mondayHoursPastWeek, equalTo(origCalendar
+                .getWorkableHours(MONDAY_LOCAL_DATE.minusWeeks(1))));
+
+        int pastSundayHours = newCalendar.getWorkableHours(MONDAY_LOCAL_DATE
+                .minusDays(1));
+        assertThat(pastSundayHours, equalTo(0));
+        assertThat(pastSundayHours, equalTo(origCalendar
+                .getWorkableHours(MONDAY_LOCAL_DATE.minusDays(1))));
+    }
+
+    @Test
+    public void testRemoveExceptionDay() {
+        BaseCalendar calendar = createChristmasCalendar();
+
+        calendar.removeExceptionDay(CHRISTMAS_DAY_LOCAL_DATE);
+
+        assertThat(calendar.getExceptions().size(), equalTo(0));
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testRemoveExceptionDayDerivedCalendar() {
+        BaseCalendar calendar = createChristmasCalendar().newDerivedCalendar();
+
+        calendar.removeExceptionDay(CHRISTMAS_DAY_LOCAL_DATE);
+    }
+
+    @Test
+    public void testRemoveExceptionDayNewVersionCalendar() {
+        BaseCalendar origCalendar = createChristmasCalendar();
+        BaseCalendar newCalendar = origCalendar.newVersion(
+                MONDAY_LOCAL_DATE);
+
+        newCalendar.removeExceptionDay(CHRISTMAS_DAY_LOCAL_DATE);
+
+        assertThat(origCalendar.getExceptions().size(), equalTo(1));
+        assertThat(newCalendar.getExceptions().size(), equalTo(0));
+    }
+
+    @Test
+    public void testGettWorkableHoursNewVersionFromChristmasCalendar() {
+        BaseCalendar origCalendar = createChristmasCalendar();
+        ExceptionDay day = ExceptionDay.create(CHRISTMAS_DAY_LOCAL_DATE
+                .plusYears(1), 0);
+        origCalendar.addExceptionDay(day);
+
+        BaseCalendar newCalendar = origCalendar
+                .newVersion(
+                CHRISTMAS_DAY_LOCAL_DATE.plusDays(1));
+
+        newCalendar
+                .updateExceptionDay(CHRISTMAS_DAY_LOCAL_DATE.plusYears(1), 8);
+
+        int christmasHours = newCalendar
+                .getWorkableHours(CHRISTMAS_DAY_LOCAL_DATE
+                .plusYears(1));
+        assertThat(christmasHours, equalTo(8));
+
+        int christmasHoursPastYear = newCalendar
+                .getWorkableHours(CHRISTMAS_DAY_LOCAL_DATE);
+        assertThat(christmasHoursPastYear, equalTo(0));
+    }
+
+    public static void setHoursForAllDays(BaseCalendar calendar, Integer hours) {
+        calendar.setMonday(hours);
+        calendar.setTuesday(hours);
+        calendar.setWednesday(hours);
+        calendar.setThursday(hours);
+        calendar.setFriday(hours);
+        calendar.setSaturday(hours);
+        calendar.setSunday(hours);
+    }
+
+    @Test
+    public void testGettWorkableHoursTwoNewVersions() {
+        BaseCalendar calendar = createBasicCalendar();
+        setHoursForAllDays(calendar, 8);
+
+        BaseCalendar calendar2 = calendar.newVersion(TUESDAY_LOCAL_DATE);
+        setHoursForAllDays(calendar2, 4);
+
+        BaseCalendar calendar3 = calendar2.newVersion(
+                FRIDAY_LOCAL_DATE);
+        setHoursForAllDays(calendar3, 2);
+
+        int hoursMonday = calendar.getWorkableHours(MONDAY_LOCAL_DATE);
+        assertThat(hoursMonday, equalTo(8));
+        assertThat(calendar2.getWorkableHours(MONDAY_LOCAL_DATE),
+                equalTo(hoursMonday));
+        assertThat(calendar3.getWorkableHours(MONDAY_LOCAL_DATE),
+                equalTo(hoursMonday));
+
+        int hoursWednesday = calendar.getWorkableHours(WEDNESDAY_LOCAL_DATE);
+        assertThat(hoursWednesday, equalTo(4));
+        assertThat(calendar2.getWorkableHours(WEDNESDAY_LOCAL_DATE),
+                equalTo(hoursWednesday));
+        assertThat(calendar3.getWorkableHours(WEDNESDAY_LOCAL_DATE),
+                equalTo(hoursWednesday));
+
+        int hoursFriday = calendar.getWorkableHours(FRIDAY_LOCAL_DATE);
+        assertThat(hoursFriday, equalTo(2));
+        assertThat(calendar2.getWorkableHours(FRIDAY_LOCAL_DATE),
+                equalTo(hoursFriday));
+        assertThat(calendar3.getWorkableHours(FRIDAY_LOCAL_DATE),
+                equalTo(hoursFriday));
+
+    }
+
+    @Test
+    public void testGettWorkableHoursDeriveAndNewVersion() {
+        BaseCalendar baseCalendar = createChristmasCalendar();
+
+        BaseCalendar calendar = baseCalendar.newDerivedCalendar();
+        setHoursForAllDays(calendar, 4);
+
+        BaseCalendar newCalendar = calendar.newVersion(WEDNESDAY_LOCAL_DATE);
+        setHoursForAllDays(newCalendar, 2);
+
+        int hoursMonday = baseCalendar.getWorkableHours(MONDAY_LOCAL_DATE);
+        assertThat(hoursMonday, equalTo(8));
+
+        hoursMonday = calendar.getWorkableHours(MONDAY_LOCAL_DATE);
+        assertThat(hoursMonday, equalTo(4));
+        assertThat(hoursMonday, equalTo(newCalendar
+                .getWorkableHours(MONDAY_LOCAL_DATE)));
+
+        int hoursFriday = baseCalendar.getWorkableHours(FRIDAY_LOCAL_DATE);
+        assertThat(hoursFriday, equalTo(8));
+
+        hoursFriday = calendar.getWorkableHours(FRIDAY_LOCAL_DATE);
+        assertThat(hoursFriday, equalTo(2));
+        assertThat(hoursFriday, equalTo(newCalendar
+                .getWorkableHours(FRIDAY_LOCAL_DATE)));
+
+        int christmasHours = newCalendar
+                .getWorkableHours(CHRISTMAS_DAY_LOCAL_DATE);
+        assertThat(christmasHours, equalTo(0));
+        assertThat(christmasHours, equalTo(calendar
+                .getWorkableHours(CHRISTMAS_DAY_LOCAL_DATE)));
+    }
+
+}
diff --git a/navalplanner-business/src/test/java/org/navalplanner/business/test/calendars/entities/ExceptionDayTest.java b/navalplanner-business/src/test/java/org/navalplanner/business/test/calendars/entities/ExceptionDayTest.java
new file mode 100644
index 000000000..05c8d26e8
--- /dev/null
+++ b/navalplanner-business/src/test/java/org/navalplanner/business/test/calendars/entities/ExceptionDayTest.java
@@ -0,0 +1,29 @@
+package org.navalplanner.business.test.calendars.entities;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.junit.Assert.assertThat;
+
+import java.util.Date;
+
+import org.joda.time.LocalDate;
+import org.junit.Test;
+import org.navalplanner.business.calendars.entities.ExceptionDay;
+
+/**
+ * Tests for {@link ExceptionDay}.
+ *
+ * @author Manuel Rego Casasnovas <mrego@igalia.com>
+ */
+public class ExceptionDayTest {
+
+    @Test
+    public void testCreateExceptionDayWithDate() {
+        Date date = new Date();
+
+        ExceptionDay day = ExceptionDay.create(date, 8);
+
+        assertThat(day.getDate(), equalTo(new LocalDate(date)));
+        assertThat(day.getHours(), equalTo(8));
+    }
+
+}