Okay, had a proper bit of playing with this and it's looking like the symbolic reference is getting the global value. As an example look at the code below.. uncomment as needed!

#!/usr/bin/perl

$::test = 'Global';
test();

sub test {
  my $test = 'Local';
  my $line = 'test';

  # This returns 'Global'.
  # print ${$line}."\n";

  # This returns 'local'
  # $line =~ s/\w+/${test}/gi;

  # This returns 'Global'
  # $line =~ s/(\w+)/${$1}/gi;

  print "$line..\n";
}
[download]

Does anyone know if this is a known thing with symbolic references? Does it effectively do a $::test?