diff --git a/navalplanner-business/src/main/resources/org/navalplanner/business/planner/entities/ResourceAllocations.hbm.xml b/navalplanner-business/src/main/resources/org/navalplanner/business/planner/entities/ResourceAllocations.hbm.xml
index 5c0b3f6af..21dc1964a 100644
--- a/navalplanner-business/src/main/resources/org/navalplanner/business/planner/entities/ResourceAllocations.hbm.xml
+++ b/navalplanner-business/src/main/resources/org/navalplanner/business/planner/entities/ResourceAllocations.hbm.xml
@@ -12,7 +12,7 @@
         </id>
         <version name="version" access="property" type="long" />
 
-        <property name="percentage" />
+        <property name="percentage" type="java.math.BigDecimal" scale="8"/>
 
         <many-to-one class="Task" name="task" column="TASK" />
 
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/ResourceAllocationController.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/ResourceAllocationController.java
index 446490e4c..60cd92967 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/ResourceAllocationController.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/ResourceAllocationController.java
@@ -307,6 +307,8 @@ public class ResourceAllocationController extends GenericForwardComposer {
             // Set percentage
             BigDecimal percentage = resourceAllocation.getPercentage();
             if (!new BigDecimal(0).equals(resourceAllocation.getPercentage())) {
+                percentage = (percentage != null) ? percentage
+                        : new BigDecimal(0);
                 percentage = percentage.scaleByPowerOfTen(2).setScale(2,
                         BigDecimal.ROUND_CEILING);
             }
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/ResourceAllocationModel.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/ResourceAllocationModel.java
index 11caccc9c..9108038b4 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/ResourceAllocationModel.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/ResourceAllocationModel.java
@@ -237,9 +237,11 @@ public class ResourceAllocationModel implements IResourceAllocationModel {
         BigDecimal result = new BigDecimal(0);
 
         for (Iterator i = resourceAllocations.iterator(); i.hasNext();) {
-            ResourceAllocation resourceAllocation = (ResourceAllocation) i
-                    .next();
-            result = result.add(resourceAllocation.getPercentage());
+            ResourceAllocation resourceAllocation = (ResourceAllocation) i.next();
+            BigDecimal percentage = (resourceAllocation.getPercentage() != null) ? resourceAllocation
+                    .getPercentage()
+                    : new BigDecimal(0);
+            result = result.add(percentage);
         }
 
         return result;