How to terminate form session after close browser in 11g envirement?

 We recently migrated our 10g to 11g. Our forms were working fine in 10g environment. In 10g, whenever the browser was closed, the forms session will be terminated at the same time. But in 11g, if we close browser without exist from form, the form session will hanging there, if login again will get "Could not reserve record(2 tries). Keep trying?" .
We setup forms_timeout=3, after close browser 3 minutes, the hanging session will gone.

But how to make the hanging session terminate right away after close the browser?

By the way, we took all the default value for all the form configuration parameter in 10g. Besides application server environment, nothing changed for the forms.