Issue in the session management java

Dear gurus

We have a double stack (ABAP+JAVA) BI and we are working with BI-IP.

We have an issue, we think due to session management, with some end-user pc. When they are planning and close java session, usually lock in SM12 remains because RFC session in SM04 are not released. It´s looks like abap stack can´t find and terminate ideling RFC session.

We opened oss message and they advice us change connection lifetime parameter to 30 sg to check if system clears SM04 and works fine for us, but there are some pc clients that its no cleared... We patched systems to the last fixpack for BI BASE and BI WEAPP but issue still remais.

Do you have any idea? We check with IE7, IE8, pop-up blocker on, pop-up blocker off...

Many thanks..

Marta