Hello zwon, thanks for your reply. I have tried to write a patch to fix this issue.

phillip@athens:~/script/Date-Handler-1.2$ cat locale.patch 
--- Handler.pm.original    2010-11-12 16:49:31.817657134 +0800
+++ Handler.pm    2010-11-12 16:42:35.153656643 +0800
@@ -541,7 +541,7 @@
 
         my $epoch = $self->{epoch};
 
-        my $newdate = ref($self)->new({ date => $epoch, time_zone => 
+$self->TimeZone() });
+        my $newdate = ref($self)->new({ date => $epoch, time_zone => 
+$self->TimeZone(), locale => $self->Locale() });
 
         my $self_array = $newdate->AsArray();
         #Take care of the months.
@@ -554,7 +554,7 @@
         $self_array->[0] += $years;
 
         my $posix_date = ref($self)->new({ date => $self_array,
-                         time_zone => $self->TimeZone(), 
+                         time_zone => $self->TimeZone(), locale => $s
+elf->Locale() 
         });
 
         if($self->INTUITIVE_MONTH_CALCULATIONS())
[download]

and I find a early mistaken in first post inwhich "Date::Handler::Delta" would not include locale and timezone. here's the modified codes and run without warning messages about locale.

#!/usr/bin/perl
#name: date.pl
    use strict;
    use warnings;
    use Date::Handler;
    use Date::Handler::Delta;

    my $delta = new Date::Handler::Delta([3,0,0,0,0,0]);

    my $date = new Date::Handler({
                        date=>time,
                        time_zone=>'Asia/Shanghai',
                        locale=>'zh_CN.utf8',
    });

    my $newdate = $date + $delta;

    print "date=$date\n";
    print "delta=$delta\n";
    print "newdate=$newdate\n";
[download]