[ADMIN] createuser error

[Dan Thompson]

I'm new to pgsql. I'm trying to install sql-ledger featured in Linux Journal
The install instructions saay to create the db admin account by:
bash$ createuser -D sql-ledger

This returns this error:
createuser: relocation error: createuser: undefined symbol: get_progname

Even if I only typ: createuser I get the exact same error.

I have read about how to create a user but I can't find where this error has popped up before.

I have made usre the database has been initialized and that the server process is running.

Any ideas?