Bacula and perl 5.20

[Andrea Venturoli]

Hello.

Bacula has some PERL scripts which have the following header:
 > #!/usr/bin/env perl

They stop working when I substitute the deprecated perl-5.16 with perl-5.20.

Right now I just change that line with:
> #!/usr/local/bin/perl

However, as someone who doesn't know PERL and just undergo it, I'm curious.
Could someone explain why this stopped working?

  bye & Thanks
	av.