I realize that this problem is mainly related to ehcache but as most users of acegi use ehcache maybe they can help me out. We have a farm of applications that are untouched for a couple of days/nights and for some reason when they are trying to login we get this message:
userCache is not alive - which means the whole authorization process goes no where. The only solution I found was to restart the application which is a no-go. It's a very wierd aspect as the cache manager should handle these issues itself and the message suggests that the cache is considered live (active) when it isn't. We are using ehcache 1.1 and acegi 0.8.3 (not that it matters).