id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
22426	Django >= 1.6.0 can't handle old style messages cookie	iivvoo	ofirov	"The message cookie format has changed in Django 1.5.x, Django 1.6.x no longer supports the old format.

If you upgrade your project from Django 1.4.x directly to 1.6.x (skipping the 1.5 release), your application will fail quickly on old-style message cookies:


{{{
 Exception Type: IndexError
 Exception Value:
 list index out of range
 Exception Location: (...) django/contrib/messages/storage/cookie.py in process_messages, line 37
}}}


Django 1.5 contained some backward compatibility to handle both styles:

https://github.com/django/django/commit/9e7183073f64e541587e8dcfd8bb3ddeb47f8162

but this code is no longer present in Django 1.6.2

Since you can't ask all your users to delete their cookies if they run into this error, there's no easy/quick workaround.

It's not uncommon for projects to skip a version. Also, Django 1.4.x is LTS and people may jump from LTS release to LTS release, which means they will also run into this issue.
"	Bug	closed	contrib.messages	1.6	Release blocker	fixed	messages, cookie, 1.4		Accepted	1	0	0	0	0	0