[Lobanak]

ok, found the problem in the howto I used http://www.howtoforge.com/suphp_debian_etch_ispconfig

there is the problem:

./configure --prefix=/usr
  --sysconfdir=/etc
  --with-apache-user=www-data
  --with-setid-mode=paranoid
  --with-apxs=/usr/bin/apxs2

If I use --with-setid-mode=owner, this works, but is not that secure.