Maybe this will help: 
use strict;
use warnings;
use Data::Dumper;

# $msglines is a reference to an array
my $msglines = [ qw(a b c) ];

# This pushes an array ref into an array,
# creating an Array-of-arrays data structure
my @msgs;
push @msgs, $msglines;

print Dumper(\@msgs);

print "Size of first array ", scalar @{ $msgs[0] }, "\n";

__END__

$VAR1 = [
          [
            'a',
            'b',
            'c'
          ]
        ];
Size of first array 3

[download]

See also:

In reply to Re: Push into an array inside a array by toolic
in thread Push into an array inside a array by baski

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