Spreadsheet::ReadSXC uses XML::Parser which properly decodes. 

$ perl -CSDA -MEncode -MXML::Parser -E'XML::Parser->new(Handlers => { 
+Char => sub { print "$_[1]" } })->parse(encode($ARGV[0], qq{<?xml ver
+sion="1.0" encoding="$ARGV[0]"?><root>\xC9ric\n</root>}));' iso-8859-
+1
Éric

$ perl -CSDA -MEncode -MXML::Parser -E'XML::Parser->new(Handlers => { 
+Char => sub { print "$_[1]" } })->parse(encode($ARGV[0], qq{<?xml ver
+sion="1.0" encoding="$ARGV[0]"?><root>\xC9ric\n</root>}));' UTF-8
Éric

[download]

Could you provide me the output from either of the following 

use Devel::Peek;
Dump($s);

[download]

or 

{
   use Data::Dumper;
   local $Data::Dumper::Useqq = 1;
   print(Dumper($s));
}

[download]

(preferably the former) for both versions of the string?

Update: Looks like you already did. I followed up there.

In reply to Re^5: One bird, two Unicode names by ikegami
in thread One bird, two Unicode names by RCH

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