pg_dump: aborting because of server version mismatch

I run omnibus gitlab on my local system postgresql server, not the embedded one. But when I try to upgrade with apt, the preinstall backup fail:

gitlab preinstall: Backing up GitLab SQL database (excluding Git repositories, uploads)
Dumping database ... 
Dumping PostgreSQL database gitlabhq_production ... pg_dump: server version: 9.3.9; pg_dump version: 9.2.9
pg_dump: aborting because of server version mismatch
[FAILED]
Backup failed
gitlab preinstall: 
gitlab preinstall: Backup failed! If you want to skip this backup, run the following command and
gitlab preinstall: try again:
gitlab preinstall: 
gitlab preinstall:   sudo touch /etc/gitlab/skip-auto-migrations
gitlab preinstall: 
dpkg: Fehler beim Bearbeiten des Archivs /var/cache/apt/archives/gitlab-ce_7.13.1-ce.0_amd64.deb (--unpack):
 Unterprozess neues pre-installation-Skript gab den Fehlerwert 1 zurück
gitlab: Thank you for installing GitLab!
gitlab: Configure and start GitLab by running the following command:
gitlab: 
gitlab: sudo gitlab-ctl reconfigure
gitlab: 
gitlab: GitLab should be reachable at http://server.office.bit3.de
gitlab: Otherwise configure GitLab for your system by editing /etc/gitlab/gitlab.rb file
gitlab: And running reconfigure again.
gitlab: 
gitlab: For a comprehensive list of configuration options please see the Omnibus GitLab readme
gitlab: https://gitlab.com/gitlab-org/omnibus-gitlab/blob/master/README.md
gitlab: 
Fehler traten auf beim Bearbeiten von:
 /var/cache/apt/archives/gitlab-ce_7.13.1-ce.0_amd64.deb

The problem is, that the preinstall script use the /opt/gitlab/embedded/bin/pg_dump instead of /usr/bin/pg_dump. When I move /opt/gitlab/embedded/bin/pg_dump away and symlink to /usr/bin/pg_dump, the install works fine.