This seems to be version specific, indicating that indeed, there was a bug / misfeature somewhere. This is what I get: 
#!/usr/local/bin/perl -w
use strict;
use Data::Dumper;
my $string="the quick brown fox";
my $packed=pack 'C/a*', $string;
my $unpacked= unpack 'C/a*', $packed;
print "'$unpacked'\n";
my @data= unpack 'C/a*', $packed;
print Dumper(\@data);
my ($len,$val)=unpack 'C/a*', $packed;
print "$len:$val\n";
__END__
'the quick brown fox'
$VAR1 = [
          'the quick brown fox'
        ];
Use of uninitialized value in concatenation (.) or string at ./packwei
+rd.pl line 11.
the quick brown fox:

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List context gets me just the text, as does scalar context. My perl is: 
Summary of my perl5 (revision 5.0 version 8 subversion 0) configuratio
+n:
  Platform:
    osname=linux, osvers=2.4.18-bv1, archname=i686-linux
    uname='linux quasimod 2.4.18-bv1 #2 tue jul 2 16:22:51 cest 2002 i
+686 unknown '

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CU
Robartes-

In reply to Re: unpack 'C/a*' and context weirdness by robartes
in thread unpack 'C/a*' and context weirdness by BrowserUk

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