Restoring backup from damaged harddisk

[voltcraft]

As I wrote in another topic (... bad performance...) my harddrive is damaged. So I did a quick backup of the zimbra directory with:

$ tar cvzf zimbra-bak.tgz /opt/zimbra

I thought it should be no problem to restore it afterwards but now I have some strange errors, here is what I did (Debian sarge system):

Extract archive:
$ tar xvzf zimbra-bak.tgz -C /opt/zimbra

Download plain release of zimbra and run setup:
./install.sh

The first strange error I got is:

bdb_db_open: db_open(/opt/zimbra/openldap-data/id2entry.bdb) failed: No such file or directory (2)
backend_startup_one: bi_db_open failed! (2)

Then the next one looked like I had no config file:

 HOSTNAME=zimbra.youthtec.at
   LDAPHOST=
   LDAPPORT=
   SNMPTRAPHOST=
   SMTPSOURCE=
   SMTPDEST=
   SNMPNOTIFY=0
   SMTPNOTIFY=0
   LDAPROOTPW=zimbra
   LDAPZIMBRAPW=zimbra

The setup stopped with a perl error.

If I like to run for example zmcontrol start I get following:

Can't locate Sys/Syslog.pm in @INC (@INC contains: /opt/zimbra/zimbramon/lib/i386-linux-thread-multi /opt/zimbra/zimbramon/lib/Zimbra/DB /opt/zimbra/zimbramon/lib/Zimbra/Mon /opt/zimbra/zimbramon/lib/Zimbra/SOAP /opt/zimbra/zimbramon/lib/i386-linux-thread-multi /opt/zimbra/zimbramon/lib /etc/perl /usr/local/lib/perl/5.8.4 /usr/local/share/perl/5.8.4 /usr/lib/perl5 /usr/share/perl5 /usr/lib/perl/5.8 /usr/share/perl/5.8 /usr/local/lib/site_perl .) at /opt/zimbra/zimbramon/lib/Zimbra/Mon/Logger.pm line 31.
BEGIN failed--compilation aborted at /opt/zimbra/zimbramon/lib/Zimbra/Mon/Logger.pm line 31.
Compilation failed in require at /opt/zimbra_old/bin/zmcontrol line 41.
BEGIN failed--compilation aborted at /opt/zimbra_old/bin/zmcontrol line 41.

Is there another way to restore "my backup"?

Which files are importent to have? Maybe I should run a fresh installation and then only replace the ldap, mysql and userdirectories?

Yours,

René