Hi Naseer,
We received your sample application and I took a quick look at it. This is just a basic application so not much that can be done to change it. I tested on 6.2.4 and I confirm the "hangup" you describe. I then tested on 6.3.14 and 6.4.0Beta2 and they both work perfectly.
So I have nothing else to offer at this point except for recommendation for upgrade to 6.3.14. Sorry about that.
Palli