[TYPO3] Cookie/Session Lifetime in 4.0

[Jeff Segars]

After upgrading to 4.0 on several sites, we've begun to notice a strange 
issue with the cookie lifetime for frontend users.

On our installs, the TYPO3_CONF_VAR for the cookie lifetime is set to 
one week.  On 3.8.1, the cookie would be set to expire in one week and 
frontend logins would persist as long as the cookie was there.

After upgrading to 4.0, the TYPO3_CONF_VAR is still set correctly and 
the cookie is correctly set to not expire for a week.  Despite this 
cookie, frontend logins quit working after a couple hours.

The cookie is still present, but it looks like the session ID stored in 
the cookie is invalid.  When I check the fe_sessions table, the ID from 
the cookie is missing.  I know garbage collection is performed on the 
sessions table, but it appears that sessions less than 24 hours old 
should not be deleted and our missing sessions are definitely under 24 
hours.

Has anyone else seen these issues with 4.0?

Thanks,
Jeff