New setting stored in $GLOBALS[‘TYPO3_CONF_VARS’][‘FE’][‘sessionDataLifetime’] defines the lifetime of frontend session data in seconds. The setting can be modified in the Install tool.
More info:
FYI24 Feature #11508: Integrate possibility to define lifetime of frontend session data
http://bugs.typo3.org/view.php?id=11508
FYI24: Feature #11510: Store timestamp of last modification of session data to frontend user object
http://bugs.typo3.org/view.php?id=11510