Hi Klaus, there are some links here to some previous discussions on ship hull modeling techniques, maybe some info and examples in those discussions would help you:
http://moi3d.com/forum/index.php?webtag=MOI&msg=3814.1

One way that I think you'll see in some of those models is to have a 90 degree rotated profile at the bow so there is a transition area from regular stations to a 90 degree rotated station at the end.

- Michael

Hi Klaus,
you can get a reasonable result by adding extra cross sections in the tip area
and loft all sections as shown in the attached photo.
If you want the file I will post it.

Barry