you introduce install zimbra step by step.
I try install zimbra on centos 5.1 not work.
tar xzvf zcs-5.0.4_GA_2101.RHEL5.20080321150546.tgz
You appear to be installing packages on a platform different
than the platform for which they were built.
This platform is CentOS5
Packages found: RHEL5
This may or may not work.
Installation can not continue without manual override.
You can override this safety check with ./install.sh --platform-override
WARNING: Bypassing this check may result in an install or
upgrade that is NOT usable.