Forms 10G Vs Forms 6I -- Mdi With Multi Screen

Dear

i have been facing this problem since 2 month ago,
my problem is:
before i start assume Forms 1 calling form , Forms 2 Called form

in forms 6i before i migrate my system to oracle forms 10g,
i was able to use open_form command inside "Forms 1" to open another form "Forms 2", the "Forms 2" form based on window of type Dialog not content, and since its dialog and i am using open form
i was able to move it outside the MDI main frame to display it on the extended desktop, But now on 10g it's not working properly
what i mean it's not moving outside the MDI its just extending
the MDI.

to be honest i don't know what causing this problem, but i have a doubt its because the Java Applet.

Please i need a solution ASAP.

With Regards