StarOffice and the Sun internally used Essbase Calc plugin are conflicting when both of them are using GTK UI and JRE 1.6. There is an issue with Java awt and the corresponding XError handler.
Here some more details about the issue from our development about the Essbase problem:
Essbase plugin wants to draw its java widgets using gtk's native drawing routines
to achieve a system like look. However since the plugin runs in a java thread when
running inside StarOffice/OpenOffice.org, this means that two threads access gtk
at the same time. This leads to problems in two ways, one of which is easily fixable.
The first problem is that the underlying X11 implementation needs to be made thread
safe by using XInitThreads. This does not happen early enough in Star/OpenOffice which
can of course easily be remedied.
The second problem however is less trivial. The second (java/Essbase) thread draws
using gtk and while using X11's APIs involuntarily gets XError events delivered.
These XErrors would normally be consumed by Star/OpenOffice's XError event handler
and handled appropriately. Gtk however sets its own XError event handler all the
time and of course has different assumptions about how to handle them; in our
case it usually ends up with the default behaviour terminating the application.
This problem cannot be fixed by Star/OpenOffice, it can also not be fixed by Essbase
plugin. The gtk specific implementation of the java awt could set its own XError
handler (which would be able to ignore XErrors while drawing widgets), however this
could generate a concurrency problem (in setting the handler by SO and java) as well
as it might not work because the very gtk methods called could reset that handler
(as gtk has shown a tendency to do). It may turn out that the only way to fix this
would be in gtk itself.