Index: src/main/java/org/jbpm/jpdl/internal/activity/TaskActivity.java
===================================================================
--- src/main/java/org/jbpm/jpdl/internal/activity/TaskActivity.java	(revision 5673)
+++ src/main/java/org/jbpm/jpdl/internal/activity/TaskActivity.java	(working copy)
@@ -28,6 +28,7 @@
 import org.jbpm.api.activity.ActivityExecution;
 import org.jbpm.api.task.Task;
 import org.jbpm.internal.log.Log;
+import org.jbpm.pvm.internal.cal.BusinessCalendar;
 import org.jbpm.pvm.internal.env.EnvironmentImpl;
 import org.jbpm.pvm.internal.history.HistoryEvent;
 import org.jbpm.pvm.internal.history.events.TaskActivityStart;
@@ -76,6 +77,12 @@
     task.setPriority(taskDefinition.getPriority());
     task.setFormResourceName(taskDefinition.getFormResourceName());
     
+    // calculate the due date of the task based on the due date duration
+    if (taskDefinition.getDueDateDuration() != null) {
+      BusinessCalendar businessCalendar = EnvironmentImpl.getFromCurrent(BusinessCalendar.class);
+      task.setDuedate(businessCalendar.add(task.getCreateTime(), taskDefinition.getDueDateDuration()));
+    }
+    
     // save task so that TaskDbSession.findTaskByExecution works for assign event listeners
     dbSession.save(task);