For Sale When expiration dates conflict!

[Johnm]

I have a question regarding registration expiration dates, especially when they are in conflict.

Which date governs the actual registration when the Whois information expiration date and the Registrar expiration date differ?

Let's take an example: sex.com:

Whois Info's listed expiration date: 17 Oct, 2010
Registrar Info's listed expiration date: 30 Nov, 2010.

These two dates are almost the same as far as we are concerned here in 2003, but they are different enough to use as an example for my question.

So would the domain expire on 17 Oct or 30 Nov? Why are they in conflict?

Thanks for any help.