Originally Posted by ixtab
5.1.1 was shipped with some newer international devices (at least most reports came from european users), but it was never publicly released for download.
5.1.1 did not fix the "web jailbreak" bug. So it was replaced with 5.1.2 with the security fix before 5.1.1 was widespread or available for download. I think we can safely ignore 5.1.1 for hacks and for debricking purposes.