max/ideal value of items in limits.conf in rhel5?

i want to set limits in /etc/security/limits.conf.My os is rhel 5.2.

It was giving continuous messages in in /var/log/secure like :

Jan 1 09:46:43 yn55 sshd[31742]: pam_limits(sshd:session): wrong limit value 'unlimited' for limit type 'soft'

Jan 1 09:46:43 yn55 sshd[31742]: pam_limits(sshd:session): wrong limit value 'unlimited' for limit type 'hard'

continuously.

I have changed values of priority and nice to "0" from unlimited and messages are not comming. But i want to know what is the ideal/maximum value of these two items? Is 0 value set is correct? To what should i set it to? I want it to be maximum.

* soft core unlimited

* hard core unlimited

* soft data unlimited

* hard data unlimited

* soft fsize unlimited

* hard fsize unlimited

* soft memlock -1

* hard memlock -1

* soft nofile 20000

* hard nofile 20000

* soft rss unlimited

* hard rss unlimited

* soft stack unlimited

* hard stack unlimited

* soft cpu unlimited

* hard cpu unlimited

* soft nproc unlimited

* hard nproc unlimited

* soft as unlimited

* hard as unlimited

* soft maxlogins unlimited

* hard maxlogins unlimited

* soft maxsyslogins unlimited

* hard maxsyslogins unlimited

* soft priority 0

* hard priority 0

* soft locks unlimited

* hard locks unlimited

* soft sigpending unlimited

* hard sigpending unlimited

* soft msgqueue unlimited

* hard msgqueue unlimited

* soft nice 0

* hard nice 0

* soft rtprio unlimited

* hard rtprio unlimited