...but I am confused as to why

Thing is that the socket which Mail::Sender is printing to, is not set up to handle Perl unicode (UTF-8) strings (as you get back from decode_entities). Whenever you print a unicode string (i.e. one that is Perl-internally flagged as unicode with the "utf8" flag on) to a filehandle/socket which is not opened for UTF-8, you'll get the "Wide character in print" warning, if the string does contain 'wide' characters (i.e. codepoint > 255).

Encode::encode('utf8', ...) essentially removes that utf8 flag, i.e. it encodes the string from the Perl-internal unicode representation into a byte string, which in this case holds the data in its proper UTF-8 encoding, but without the utf8 flag set. That's why you're no longer getting the warning from Mail::Sender — because in a byte string, no value is > 255.   (As already implied, Mail::Sender hasn't been written to accept unicode strings, even if you declare charset to be 'utf8'.)

If you want to explore this further, you could look into Mail::Sender's Connect routine (line 934), where the socket is being opened. If you'd add (for testing purposes) 

    binmode($s, ":utf8");

[download]

before the return $s; ($s is the socket), my prediction would be that you'd no longer need to Encode::encode your $input. Just in case you feel like playing around... :)

In reply to Re^3: Wide characters in e-mail by almut
in thread Wide characters in e-mail by lghansen

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