Now, I remember reading somewhere that decoding in Perl was actually the same as encoding in utf-8
Not true. 
use strict;
use warnings;
use utf8;
use Encode qw(encode_utf8);

binmode STDOUT, ':encoding(UTF-8)';

my $s = "sämple\n";
print uc $s;
print uc encode_utf8($s);
__END__
Output:
SÄMPLE
SäMPLE

[download]

Note that the use utf8; implicitly decodes string constants in this program.

is it as simple as decoding each element individually before using it?

Yes.

Would I then need to re-encode it or should setting the charset in the content type for the email be sufficient?

You should give your decoded string to a module that does the encoding for you. No need to re-invent the wheel.

In reply to Re^3: strange utf-8 (I think) behaviour... by moritz
in thread strange utf-8 (I think) behaviour... by seekay

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