It might be easier to upgrade your perl to 5.14: 
$ perl-5.14.2 -wE 'say "\xA0" =~ /\s/'
1
$ perl-5.14.2 -wle 'print "\xA0" =~ /\s/u'
1
$ perl-5.12.2 -wE 'say "\xA0" =~ /\s/'

$

[download]
Alternatively, upgrade your string to UTF-8: 
$ perl -wle '$_ = chr 0xA0; utf8::upgrade($_); print /\s/'
1
$

[download]

In reply to Re: Can I change \s? by JavaFan
in thread Can I change \s? by pileofrogs

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