exchange 2010 changing time zone not updated

I have changed my cas/hub servers time zone to my location city. But when I request a read notification from a user in my exchange I still see the old timezone of  the old city that was set. I have restarted the Microsoft exchange transport service, but did not make a change. Do I need to reboot or is there any way I can update this to the exchange server. Ex 2010 sp2