Error when deleting multiple databases: "Maintenance database can't be dropped."

Hello,

When selecting multiple databases (via the "Properties" tab) and trying to
delete them, only the first one gets deleted, and then an error pops up.

The question:

Drop multiple objects?
Are you sure you wish to drop multiple objects?

The error:

Dropping database not allowed
Maintenance database can't be dropped.

The "maintenance database" is not selected.

This is with pgadmin3 1.20.0-1 from Debian (the experimental repo), but
happens with 1.18.1-3, too.

The system is Ubuntu 14.04.

I am using libwxgtk3.0-0=3.0.2-1 and libwxbase3.0-0=3.0.2-1 (upgraded for
pgadmin3 1.20).

I think it might be related to having installed the postgresql-contrib package
and using the "Fix it!" button from the wizard that recommends this when
selecting the "postgres" database.
If I remember correctly, this used to work before - and I've suspected it to
be a regression in 1.20 (which I've just upgraded to also), but then the bug
is now also there with 1.18.

Thanks,
Daniel.

--
http://daniel.hahler.de/