Just thought of yet another better way of explainig it.

In Debian - which is a package management system like CPAN, your package depends on another package, maybe with a minimum version number, but as a package name.

You can write your own packages, download them manually, and manually install them - but there is no way for the package management system to do that - it is always going to install a package by its identifier - in this case name.

To get around this a special release of a package will often be required - eg: with some special patches, maybe a newer version, maybe just because it had to be built differently (eg: with different threading model).

In every case - it is given a new name.

Scott