RTF is fundamentally a ANSI text file. A character set specification is used to set the code page used and may be one of:

• \ansi - the default
• \mac - Apple Macintosh
• \pc - IBM(R) PC Code Page 437
• \pca - IBM PC Code Page 850

However the encoded characters you show suggests that the code page being used is compatible with cp1252 (the wikipedia article's mention of cp1256 is misleading and wrong as far as I can tell). The following may be the voodoo you are looking for:

use strict;
use warnings;
use Encode;

my $x = "foo à, è, ì, ò, ù bar";
my $x1 = encode('cp1252', $x);

$x1 =~ s<([\x00-\x1F\x7F-\xFF])> <"\\'" .(unpack("H2",$1))>eg;

print $x1;
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