"New name" never printing has nothing to do with passing by reference ($self is already reference to the object) and everything to do with how threads work. For more information on this topic by a monk with a similar problem, please see Shared variable not changing?.

Just to reinforce the point that the blessed object reference (what is stored in $self) can be used to reset the name when threading doesn't get in the way, consider this example using a closure:

{
  package Foo;
  sub new {
    my $sClass = shift;
    my $self= { name => shift };
    return bless($self, $sClass);
  }
  sub printName {
    my $self = shift;
    print $self->{name} . "\n";
  };
}

my $oFoo = Foo->new(q{George Alan O'Dowd});
my $crPrintCurrentName = sub { $oFoo->printName(); };

&$crPrintCurrentName();
$oFoo->{name} = 'Boy George';
&$crPrintCurrentName();
[download]

prints

George Alan O'Dowd
Boy George
[download]

Best, beth