hmmm, I think it's fairly common practice amongst similar software (i.e. firefox, chrome, etc.) to use system time as a signal that you may be connecting to a server that has an outdated SSL certificate. while it's not perfect, it's a good first order security precaution to take (in addition to verifying the CA) to ensure you are talking to who you think you are.
Certificate validation for 802.1x networks relies on this, with the effect that you sometimes can't get an internet connection without fixing your clock.