This does not seem to work.

The GD:: namespace is not copying over... The Hackmare::GD namespace is getting pointed to the GD::Image namespace when the GD::Image copy takes place. I tried both:

*Hackmare::GD::Image::new = \&GD::Image::new;
and
*Hackmare::GD::Image:: = GD::Image::;
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. Here is the debug output if it helps at all...

*Hackmare::GD::Image::new = \&GD::Image::new;
*GD::Image:: = *SVG::GD::Image::;

package SVG::GD::Image;

#constructor
sub SVG::GD::Image::new {
    my $class = shift;
    my $self = {};
    bless $self, $class;
    $self->{_GD_} = new Hackmare::GD::Image(@_)
        || print STDERR "Quitting. Unable to construct new GD::Image
    object using GD: $!\n";

    ....stuff....    

    return $self
}
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Here is the debugging info: Notice the infinite loop for the constructor:

main::(test/18-loadsvggd.pl:6): print "Creating an SVG::GD Image\n";
  DB<0> 
Creating an SVG::GD Image
main::(test/18-loadsvggd.pl:7): my ($width,$height) = (200,200);
  DB<0> 
main::(test/18-loadsvggd.pl:8): my $dwg = new GD::Image($width,$height
+);
  DB<0> s
SVG::GD::Image::new(SVG/GD.pm:79):          my $class = shift;
  DB<0> s
SVG::GD::Image::new(SVG/GD.pm:80):          my $self = {};
  DB<0> 
SVG::GD::Image::new(SVG/GD.pm:81):          bless $self, $class;
  DB<0> 
SVG::GD::Image::new(SVG/GD.pm:82):          $self->{_GD_} = new Hackma
+re::GD::Image(@_) 
SVG::GD::Image::new(SVG/GD.pm:83):                  || print STDERR  "
+Quitting. Unable to construct new GD::Image
SVG::GD::Image::new(SVG/GD.pm:84):              object using GD: $!\n"
+;
  DB<0> s
GD::Image::new(SVG/GD.pm:79):       my $class = shift;
  DB<0> 
GD::Image::new(SVG/GD.pm:80):           my $self = {};
  DB<0> 
GD::Image::new(SVG/GD.pm:81):       bless $self, $class;
  DB<0> 
GD::Image::new(SVG/GD.pm:82):           $self->{_GD_} = new Hackmare::
+GD::Image(@_) 
GD::Image::new(SVG/GD.pm:83):                   || print STDERR "Quitt
+ing. Unable to construct new GD::Image
GD::Image::new(SVG/GD.pm:84):           object using GD: $!\n";
  DB<0> 
GD::Image::new(SVG/GD.pm:79):       my $class = shift;
  DB<0> 
GD::Image::new(SVG/GD.pm:80):           my $self = {};
  DB<0> 
GD::Image::new(SVG/GD.pm:81):       bless $self, $class;
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Is anything glaringly obvious here?