Moe is the beginnings of an implementation of Perl 5 on the JVM (written in Scala). By design it's going to diverge from the standard Perl implementation somewhat, though there should ultimately be a common subset of Perl which runs in both.

The Rakudo implementation of Perl 6 currently runs on top of the Parrot virtual machine, but is in the process of being ported onto the JVM.

Update: Perlito 6 also has an experimental Perl 6 to Java translator.