Fix crasher

Add missing 'use' and use get/set method for cleaner storage of QP object

lib/Qpsmtpd.pm

@@ -5,6 +5,7 @@ use vars qw($TraceLevel $Spool_dir $Size_threshold);
 
 use Sys::Hostname;
 use Qpsmtpd::Constants;
+use Qpsmtpd::Address;
 
 our $VERSION = "0.94";
 
@@ -651,7 +652,7 @@ sub auth_mechanism {
 sub address {
     my $self = shift;
     my $addr = Qpsmtpd::Address->new(@_);
-    $addr->{qp} = $self;
+    $addr->qp($self);
     return $addr;
 }
 

lib/Qpsmtpd/Address.pm

@@ -346,7 +346,8 @@ hook_user_config
 =cut
 
 sub qp {
-    my ($self) = @_;
+    my $self = shift;
+    $self->{qp} = $_[0] if @_;
     return $self->{qp};
 }