sub check_invoicing_list {
my( $self, $arrayref ) = @_;
foreach my $address ( @{$arrayref} ) {
+
+ if ($address eq 'FAX' and $self->getfield('fax') eq '') {
+ return 'Can\'t add FAX invoice destination with a blank FAX number.';
+ }
+
my $cust_main_invoice = new FS::cust_main_invoice ( {
'custnum' => $self->custnum,
'dest' => $address,