Really weird, looks like a bug:
use Test::More;

ok( 1 =~ m/\p{Nd}/ );
ok( 1 =~ m/^-?\p{Nd}/ );
ok( 1 =~ m/-?\p{Nd}+/ );

ok( 1 =~ m/-?\p{Nd}/ );
ok( 1 =~ m/-*\p{Nd}/ );
ok( 1 =~ m/x?\p{Nd}/ );
ok( 1 =~ m/x?y?\p{Nd}/ );

done_testing();

__END__
ok 1
ok 2
ok 3
not ok 4
#   Failed test at ./t.pl line 16.
not ok 5
#   Failed test at ./t.pl line 17.
not ok 6
#   Failed test at ./t.pl line 18.
not ok 7
#   Failed test at ./t.pl line 19.
1..7
# Looks like you failed 4 tests of 7.

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$ perl -v

This is perl, v5.10.0 built for darwin-thread-multi-2level

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In reply to Re: Simple regex should match number by repellent
in thread Simple regex should match number by Anonymous Monk

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