Here's another simple solution 
my $s = "012345678901234567890123456789";
print $s, "\n";
$i=0;
$s =~ s/(\d{5})/$1.(++$i==3 && "<BR>" or $i!=6 && "-")/ge;
print $s, "\n";

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In reply to Re: A regex question... by fletcher_the_dog
in thread A regex question... by thezip

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