B::Deobfuscate is a backend module for the Perl compiler that generates perl
source code, based on the internal compiled structure that perl itself creates
after parsing a program. It adds symbol renaming functions to the B::Deparse
module. An obfuscated program is already parsed and interpreted correctly by
the B::Deparse program. Unfortunately, if the obfuscation involved variable
renaming then the resulting program also has obfuscated symbols.

WWW: http://search.cpan.org/dist/B-Deobfuscate/