As described earlier in http://forums.activiti.org/en/viewtopic.php?f=6&t=3170
Use the attached process to reproduce the issue below.
When the execution leaves the fork inclusive gateway, tasks A, B and C are created ("Task C" is a call activity with just one user task).
1. I perform "Task A" and the join inclusive gateway keeps waiting.
2. I perform "Task B" and the join inclusive gateway leaves, creating "Task D".
3. I perform "Task C" and another "Task D" is created.
4. I ended up having two instances of "Task D".
The gateway should join tasks A, B and C before reaching "Task D".