Postgresql is vrij irritant om in te komen als root:

[Syn-3] root@demo.syn-3.eu /etc/openxchange# su - postgresql
No directory, logging in with HOME=/
/dev/pts/22: Operation not permitted

Never do today what you can put off until tomorrow.

[Syn-3] postgresql@demo.syn-3.eu /$ dropdb openxchange
DROP DATABASE
[Syn-3] postgresql@demo.syn-3.eu /$ dropuser openxchange
DROP USER
[Syn-3] postgresql@demo.syn-3.eu /$ psql
Welcome to psql 7.4.8, the PostgreSQL interactive terminal.

Type:  \copyright for distribution terms
       \h for help with SQL commands
       \? for help on internal slash commands
       \g or terminate with semicolon to execute query
       \q to quit

postgresql=#