The Demo package:
#!perl -w

package Demo;
use strict;
my @handle;

    
sub new {
my $class = shift;
my $id = shift;
$handle[$id] = bless {string => shift},$class;
print "new $handle[$id]->{string}";    
return $id;
    }


sub string{
my $self = shift;
my $id = shift;
print "id = $id, handle string = $handle[$id]->{string}\n";
if (@_) {
   $handle[$id]->{string} = shift;
}
return $handle[$id]->{string};
}

sub get{
my $self=shift;
my $id = shift;
if ($handle[$id] == undef) {
   print "not defined!";
   $self->new($id,"undefined");
}

return $id;
}
1;

The server:
#!perl -w
use SOAP::Transport::HTTP;
use Demo;
use strict;
  my $daemon = SOAP::Transport::HTTP::Daemon
    -> new (LocalPort => 90)
    -> dispatch_to('Demo')
  ;
  print "Contact to SOAP server at ", $daemon->url, "\n";
  $daemon->handle;

The first client:

#!perl -w
use strict;  
    
  use SOAP::Lite +autodispatch =>
    uri => 'Demo',
    proxy => ('http://localhost:90/soap/server.pl');
    
my $demo = Demo->new(1,"test1a");

print Demo->string(1) . "\n";

Demo->string(1,"test1b");

print Demo->string(1) . "\n";

and the second client that demonstates that the data has benn cached:

#!perl -w
use strict;  
    
  use SOAP::Lite +autodispatch =>
    uri => 'Demo',
    proxy => ('http://localhost:90/soap/server.pl');
    
my $demo = Demo->get(1);

print Demo->string(1) . "\n";

Demo->string(1,"test 2");

print Demo->string(1) . "\n";