Perl 4 is gone? Someone must have a copy of it lying around if you wish to still use it. :-)

Perl is open source; no one is making anyone upgrade. If no one uses Perl 4 anymore, I think it's more a case that the people have "voted with their feet" and migrated to Perl 5 due to its suitedness for general programming.

No one speaks Latin anymore either.. languages evolve and change to suit the needs of the speakers.