Win32::Mutex works ok for using the same version perl as you?

#! perl -slw
use strict;
use Win32::Mutex;

#! backslashes are prohibited in mutex names
(my $name = $0) =~ tr[\\][/]; 

my $mtx = Win32::Mutex->open($name);
die "$0 is already running" if $mtx;

$mtx = Win32::Mutex::->new(1,$name) or die $^E;
print "process id: $$";
sleep 1000;
__END__
c:\test>perl -v
This is perl, v5.6.1 built for MSWin32-x86-multi-thread
Binary build 633 provided by ActiveState Corp. http://www.ActiveState.
+com
...
c:\test>mutex
process id: 200
^C
c:\test>^C
c:\test>start /b mutex

c:\test>process id: 218
mutex
C:\test\mutex.pl is already running at C:\test\mutex.pl line 7.

c:\test>kill 218

c:\test>mutex
process id: 271
^C
c:\test>^C
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