[CentOS] Linux HA or Heartbeat IP address question

Hi all,

I am following the guide on HowToForge to get Heartbeat going for two
Apache web servers
(http://www.howtoforge.com/high_availability_heartbeat_centos), a
quick question for anyone who might have a similar setup.

Do I have to assign the service IP to either of the NICs or does
Heartbeat do that automagically?

Thanks

-- 
"The secret impresses no-one, the trick you use it for is everything"
- Alfred Borden (The Prestiege)