Seems more likely that Sabre's restriction was because old phone dials (and the keypads that replaced them) didn't have Q or Z: http://payphonepictures.com/446

Seems more likely that Sabre's restriction was because old phone dials (and the keypads that replaced them) didn't have Q or Z: http://payphonepictures.com/44631-4/IMG_4953.jpg http://payphonepictures.com/44631-4/IMG_4953.jpg http://www.dreamstime.com/royalty-free-stock-photography-pay-phone-keypad-image1938827 http://www.dreamstime.com/royalty-free-stock-photography-pay...