This one is an easy fix with a jailbreak tweak called xCon.
Xcon is a Cydia tweak that will fool Amazon and other Apps to work on your jailbroken iPad. Not many native iOS apps block your device for being jailbroken, but some have been targeting and blocking jailbroken devices from access. Bloomberg Anywhere, Cablevision, Cisco M-Learning, DirecTV iPad and Time Warner Cable are blocking your jailbroken iPad and iPhone from access.
The developer of xCon is maintaining this tweak as the catch-all for blocked app content, being quict happy to extend the supported list for jailbreakers.