Incorrect choice of "database name suggestion" when installing scripts

There's a little issue with name suggestion for automatically created databases upon installing scripts.

All is okay as long as the default name "firstpartofdomainname_scriptname" is available (not yet present).

But as soon as the installer needs to make an alternate choice, because the default name already exists, things go wrong. :) Example:

Domain "example.com". I install "mantis" with no existing DBs. Default choice "example_mantis" presented and accepted.

I create an empty database "example_mediawiki". Then try to install MediaWiki. Name choice is now "example_mantis_mediawiki". Uuhm, unfortunate naming somewhat. :)

Then I try to install "wordpress", WITHOUT creating any "obstacle database". Name choice is "example_mantis_wordpress" even though "example_wordpress" is available.

This scheme continues (names get longer and longer) with each "obstacle" I create.