You sure? It must not be a utf string (you may need to decode it, see Re: iso-8859-1 code converter).

C:\>perl -e"print unpack q!H*!, chr 333"
c58d
C:\>perl -e"print ord chr 333"
333
C:\>perl -e"print chr 333"
Wide character in print at -e line 1.
+ì
C:\>perl -MEncode -e"print ord decode q!UTF-8!,encode q!UTF8!,chr 333"
333
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ō
Unicode Character 'LATIN SMALL LETTER O WITH MACRON' (U+014D)
http://perl5.git.perl.org/perl.git/blob?f=t/op/ord.t