Ok, a step further. petabyte from merusers.de pointed me to
http://wiki.navit-project.org/index....chbox_for_N8x0
This site has now instructions to compile Navit for the N900.
With these fixes I was able to overcome the crash.
Navit starts, runs really slow (cache disables), GTK is usable, Internal too slow.
But does not focus according to my GSM postion. I'm indoor so no GPS avaliable.

A small screenshot: