Got the same problem and this is what i get when i run DEBCONF_DEBUG="developer" dpkg --configure -a

I've tried to run apt-get install -reinstall postfix but with no luck.

root@srv01:~# DEBCONF_DEBUG="developer" dpkg --configure -a
Setting up postfix (2.5.5-1.1) ...
debconf (developer): frontend started
debconf (developer): frontend running, package name is postfix
debconf (developer): starting /var/lib/dpkg/info/postfix.config configure 2.5.5-1.1
debconf (developer): <-- VERSION 2
debconf (developer): --> 0 2.0
debconf (developer): <-- CAPB backup
debconf (developer): --> 0 multiselect escape backup
debconf (developer): <-- TITLE Postfix Configuration
debconf (developer): --> 0
debconf (developer): <-- FGET postfix/main_mailer_type isdefault
debconf (developer): The isdefault flag is deprecated, use the seen flag instead
debconf (developer): --> 0 false
debconf (developer): <-- INPUT high postfix/main_mailer_type
debconf (developer): --> 30 question skipped
debconf (developer): <-- GET postfix/main_mailer_type
debconf (developer): --> 0 Internet Site
debconf (developer): <-- FGET postfix/mailname isdefault
debconf (developer): The isdefault flag is deprecated, use the seen flag instead
debconf (developer): --> 0 false
debconf (developer): <-- INPUT high postfix/mailname
debconf (developer): --> 30 question skipped
debconf (developer): <-- GET postfix/main_mailer_type
debconf (developer): --> 0 Internet Site
debconf (developer): <-- FGET postfix/root_address isdefault
debconf (developer): The isdefault flag is deprecated, use the seen flag instead
debconf (developer): --> 0 false
debconf (developer): <-- INPUT medium postfix/root_address
debconf (developer): --> 30 question skipped
debconf (developer): <-- GET postfix/main_mailer_type
debconf (developer): --> 0 Internet Site
debconf (developer): <-- GET postfix/mailname
debconf (developer): --> 0 srv1.ergeni.com.mk
debconf (developer): <-- FGET postfix/destinations set
debconf (developer): --> 0 true
debconf (developer): <-- SET postfix/destinations srv01.ergeni.com.mk, ergeni.com.mk, localhost.ergeni.com.mk, localhost
debconf (developer): --> 0 value set
debconf (developer): <-- INPUT medium postfix/destinations
debconf (developer): --> 30 question skipped
debconf (developer): <-- INPUT medium postfix/chattr
debconf (developer): --> 30 question skipped
debconf (developer): <-- SET postfix/mynetworks 127.0.0.0/8
debconf (developer): --> 0 value set
debconf (developer): <-- INPUT low postfix/mynetworks
debconf (developer): --> 30 question skipped
debconf (developer): <-- FGET postfix/procmail isdefault
debconf (developer): The isdefault flag is deprecated, use the seen flag instead
debconf (developer): --> 0 false
debconf (developer): <-- INPUT low postfix/procmail
debconf (developer): --> 30 question skipped
debconf (developer): <-- INPUT low postfix/mailbox_limit
debconf (developer): --> 30 question skipped
debconf (developer): <-- INPUT low postfix/recipient_delim
debconf (developer): --> 30 question skipped
debconf (developer): <-- SET postfix/protocols all
debconf (developer): --> 0 value set
debconf (developer): <-- INPUT low postfix/protocols
debconf (developer): --> 30 question skipped
debconf (developer): starting /var/lib/dpkg/info/postfix.postinst configure 2.5.5-1.1
debconf (developer): <-- FGET postfix/chattr changed
debconf (developer): --> 0 false
debconf (developer): <-- GET postfix/main_mailer_type
debconf (developer): --> 0 Internet Site
debconf (developer): <-- FGET postfix/mailname changed
debconf (developer): --> 0 false
debconf (developer): <-- FGET postfix/destinations changed
debconf (developer): --> 0 false
debconf (developer): <-- FGET postfix/relayhost changed
debconf (developer): --> 0 false
debconf (developer): <-- FGET postfix/mynetworks changed
debconf (developer): --> 0 false
debconf (developer): <-- FGET postfix/procmail changed
debconf (developer): --> 0 false
debconf (developer): <-- FGET postfix/mailbox_limit changed
debconf (developer): --> 0 false
debconf (developer): <-- FGET postfix/recipient_delim changed
debconf (developer): --> 0 false
debconf (developer): <-- FGET postfix/main_mailer_type changed
debconf (developer): --> 0 false
debconf (developer): <-- FGET postfix/protocols changed
debconf (developer): --> 0 true
debconf (developer): <-- GET postfix/protocols
debconf (developer): --> 0 all
setting inet_protocols: all
debconf (developer): <-- FGET postfix/root_address changed
debconf (developer): --> 0 false
debconf (developer): <-- FSET postfix/main_mailer_type changed false
debconf (developer): --> 0 false
debconf (developer): <-- FSET postfix/root_address changed false
debconf (developer): --> 0 false
debconf (developer): <-- FSET postfix/destinations changed false
debconf (developer): --> 0 false
debconf (developer): <-- FSET postfix/mailname changed false
debconf (developer): --> 0 false
debconf (developer): <-- FSET postfix/relayhost changed false
debconf (developer): --> 0 false
debconf (developer): <-- FSET postfix/chattr changed false
debconf (developer): --> 0 false
debconf (developer): <-- FSET postfix/mynetworks changed false
debconf (developer): --> 0 false
debconf (developer): <-- FSET postfix/procmail changed false
debconf (developer): --> 0 false
debconf (developer): <-- FSET postfix/mailbox_limit changed false
debconf (developer): --> 0 false
debconf (developer): <-- FSET postfix/recipient_delim changed false
debconf (developer): --> 0 false

Postfix is now set up with the changes above.  If you need to make changes, edit
/etc/postfix/main.cf (and others) as needed.  To view Postfix configuration
values, see postconf(1).

After modifying main.cf, be sure to run '/etc/init.d/postfix reload'.

debconf (developer): <-- STOP
Running newaliases
 * Stopping Postfix Mail Transport Agent postfix                                   [ OK ]
 * Starting Postfix Mail Transport Agent postfix                                          
postfix: fatal: /etc/postfix/postfix-script: No such file or directory
                                                                                   [fail]
invoke-rc.d: initscript postfix, action "restart" failed.
dpkg: error processing postfix (--configure):
 subprocess post-installation script returned error exit status 1
Processing triggers for libc6 ...
ldconfig deferred processing now taking place
Errors were encountered while processing:
 postfix