diff --git a/jbpm-human-task/jbpm-human-task-jpa/src/main/java/org/jbpm/services/task/persistence/TaskTransactionInterceptor.java b/jbpm-human-task/jbpm-human-task-jpa/src/main/java/org/jbpm/services/task/persistence/TaskTransactionInterceptor.java
index <HASH>..<HASH> 100644
--- a/jbpm-human-task/jbpm-human-task-jpa/src/main/java/org/jbpm/services/task/persistence/TaskTransactionInterceptor.java
+++ b/jbpm-human-task/jbpm-human-task-jpa/src/main/java/org/jbpm/services/task/persistence/TaskTransactionInterceptor.java
@@ -42,7 +42,7 @@ public class TaskTransactionInterceptor extends AbstractInterceptor {
     }
 	
 	@Override
-	public <T> T execute(Command<T> command) {
+	public synchronized <T> T execute(Command<T> command) {
 		boolean transactionOwner = false;
 		T result = null;
JBPM-<I> - Make HumanTask transaction interceptor thread safe