jbuilder 2007 does NOT parse valid GUI forms created by old jbuilder

[alskor]

new Jbuilder 2007 has a regression in GUI designer:
it does not parse old forms (created in previous jbuilder versions) properly in most cases.
note: these forms are shown correctly in previous jbuilder versions (2005, 2006).

Steps to Reproduce:
Start any previous JBuilder version, like 2006.
create a swing application,
create a frame/panel, open it in "Design" mode.
add something more or less complicated to the form.
note: the frame/panel is parsed and shown properly.

start JBuilder 2007,
import the application.
open the created frame/panel in the "visual editor".

expected: the frame/panel is displayed properly like in the previous jbuilder versions

actual:
the form is not shown,
sometimes components are displayed independently of each other (not one inside other),
sometimes nothing is shown in the editor,
or even NullPointerException is displayed.
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is this a known problem?