Call several external Windows with one(!) click

Hello , I have a list of external URL's wich I want to show with one "Click".

So I defined a Button in a view with following coding:

method onactionCLICK.

... filling internal table with URL's.....

loop at itab int wa.

call method l_window_manager->create_external_window

exporting

url = wa-url

receiving

window = l_window.

l_window->open( ).

endloop.

endmethod.

The Problem is, that only one(!) window appears with the last URL.

Any ideas ?

Greeting T.Kroepelin