Thanks for replay. Here is command output:
#ls -l /bin/sh
lrwxrwxrwx 1 root root 9 Feb 8 22:17 /bin/sh -> /bin/bash
Yesterday I found that Ubuntu 7.10 probably has build in AppArmor feature. From /var/log/messages:
AppArmor: AppArmor initialized<5>audit(1202899231.350:2): type=1505 info="AppArmor initialized" pid=1055
So I disabled it as described on https://help.ubuntu.com/community/AppArmor
and reinstalled ispconfig again. Unfortunately AppArmor was up again after restart even if I disabled it as described on help page. I have to kill it before installation.
For now it seems ok but will see for some more testing. After last reinstallation it was ok too but next day error was back.
With disabling AppArmor gone away follow bind error message too:
Failure registering capabilities with primary security module.