If the problem is that he forgot to encode his XML, the solution is NOT to get the length of the internal representation of the XML, it's to encode the XML. 
use Encode qw( encode );
# Or whatever encoding you specified in <?xml?>
$xmldata = encode('UTF-8', $xmldata);
my $length = length( $xmldata );

[download]
or 
utf8::encode( $xmldata );
my $length = length( $xmldata );

[download]

In reply to Re^4: Determining content-length for an HTTP Post by ikegami
in thread Determining content-length for an HTTP Post by Anonymous Monk

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