One regex-less way to do this is to split around the (.) into an array and join the elements back; 
use strict;
use warnings;
my $string = "Kev.has.a.stupid.perl.question";
my @array = split /\./, $string;
my $fixed = join('\.',@array);
print $fixed;

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Though, your regex $text =~ s/\./\\./g; seems to can work fine!.

update: added links and a bit of details

Excellence is an Endeavor of Persistence. A Year-Old Monk :D .

In reply to Re: Incredibly stupid substitution question :( by biohisham
in thread Incredibly stupid substitution question :( by viffer

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