pdf: Ensure a paper size is set

include/class.ticket.php

@@ -1664,7 +1664,13 @@ class Ticket {
 
     //Print ticket... export the ticket thread as PDF.
     function pdfExport($psize='Letter', $notes=false) {
+        global $thisstaff;
+
         require_once(INCLUDE_DIR.'class.pdf.php');
+        if (!is_string($psize))
+            if (!$thisstaff || !($psize = $thisstaff->getDefaultPaperSize()))
+                $psize = 'Letter';
+
         $pdf = new Ticket2PDF($this, $psize, $notes);
         $name='Ticket-'.$this->getExtId().'.pdf';
         $pdf->Output($name, 'I');