Zaxo's solution actually does work.  I think you've made a mistake in the way you pass the data to Data::Dumper.

You need to pass a reference to the hash, not just the hash itself.

Try this:

use strict;
use warnings;
use Data::Dumper;

# Pretend that I've already read the file into @lines ...
my @lines = (
    'A, B, C',
    'D,E,F',
    'G, H,I',
);

# Zaxo's solution
my %hash = map { chomp; split ',', $_, 2 } @lines;

# View the data (use a *reference* to the hash, though!)
printf "Data => %s\n", Dumper(\%hash);
[download]

which correctly outputs the following...

Data => $VAR1 = {
          'A' => ' B, C',
          'D' => 'E,F',
          'G' => ' H,I'
        };
[download]