PROBLEM/ABSTRACT:
When performing a 5.x upgrade from 4.x, the 5.x installer fails with a "Non-standard database install detected" error followed by either a "Database datafiles are in a non-standard location" message or a "Database binaries are in a non-standard location" message.

SOLUTION:
You may get this message if an install was interrupted before it completed which left the installation in an unknown, partially installed state. This could also happen if a previous install failed due to having a locale on the machine that was not UTF8-compliant. If the solution is not apparent, your first course of action would be to remove the following "DB_*" entries from the acserver.cnf and reinstall:

DB_DRIVER = Postgres
DB_CONNECT = localhost:5075@accurev
DB_USER = acserver
DB_PASS = e8c5ed8f07bfaf44d25129ec4e868626
DB_HOME = /opt/accurev/postgresql

If that fails to resolve the problem, your best course of action may be to uninstall (be sure there's a backup of the storage directory first) and go through the full install procedure again.