Running this script on Solaris

#!/usr/local/bin/perl -w

use strict;

print "[", scalar test('abc'), "]\n";
print "[", test('abc'), "]\n";
print "[", scalar test('123'), "]\n";
print "[", test('123'), "]\n";

sub test {
    my @rv = $_[0] =~ /^([0-9]+)$/;
    return @rv[ 0 .. $#rv ];
}
[download]

michael$ perl t.pl
[[]
[]
[123]
[123]
michael:$ perl -v
This is perl, v5.6.1 built for sun4-solaris

Copyright 1987-2001, Larry Wall

Perl may be copied only under the terms of either the Artistic License
+ or the
GNU General Public License, which may be found in the Perl 5 source ki
+t.

Complete documentation for Perl, including FAQ lists, should be found 
+on
this system using `man perl' or `perldoc perl'.  If you have access to
+ the
Internet, point your browser at http://www.perl.com/, the Perl Home Pa
+ge.
[download]

michael$ /usr/local/bin/perl t.pl
[[]
[]
[123]
[123]

michael$ /usr/local/bin/perl -v  

This is perl, version 5.005_03 built for sun4-solaris

Copyright 1987-1999, Larry Wall

Perl may be copied only under the terms of either the Artistic License
+ or the
GNU General Public License, which may be found in the Perl 5.0 source 
+kit.

Complete documentation for Perl, including FAQ lists, should be found 
+on
this system using `man perl' or `perldoc perl'.  If you have access to
+ the
Internet, point your browser at http://www.perl.com/, the Perl Home Pa
+ge.
[download]

There were no warnings, I get them when running under 5.10.0