{       
    eval "package $pkg;"; 
    no strict 'refs';
    *{$pkg . '::new'} = sub {        
        (shift)->SUPER::new(%{$fields}) 
    };
}

##</code><code>##

{
    no strict 'refs';
    *{$pkg . '::new'} = sub { 
        eval "package $pkg;";        
        (shift)->SUPER::new(%{$fields}) 
    };
}