And here's what I came up 
sub make_sort_order {
	my $str = shift;
	$str =~
	tr(aáàảãạăaáàảãạăắằẳẵặâấầẩẫậbcdđeéèẻẽẹêếềểễệfghiíìỉĩịjklmnoóòỏõọôốồổỗộơớờởỡợpqrstuúùủũụưứừửữựvwxyýỳỷỹỵz)
	  (00000011111111111112222223456777777888888abcddddddefghijjjjjjkkkkkkllllllmnopqrrrrrrsssssstuvwwwwwwx)d;

	return $str;
}

my @words = ('ầm', 'ãm', 'ấm chè', 'ám số');


print $_->[1], "[n" for
	sort { $a->[0] cmp $b->[0] || $a->[1] cmp $b->[1] }
	map  { [ make_sort_order($_), $_ ] } @words;

It's still missing a correct 'secondary sort' (for the edge case when the diacritic-stripped words are identical); it should not be difficult to add once someone figures out a suitable transliteration that sorts asciibetically.

In reply to Re^2: Sorting Vietnamese text by Anonymous Monk
in thread Sorting Vietnamese text by pdenisowski

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