64 Bit OS
ZCS will run on RHEL 4 x86_64, with 32bit compat installed. Some work is required to make the Zimbra perl scripts function though. The perl modules included with Zimbra are 32bit. Change the Zimbra users Perl @INC var and make sure all the needed modules are available in the RHEL 64bit Perl install.
If the mta won't start, make sure that the libraries are being found:
If you get errors like:
/opt/zimbra/postfix-2.2.5/sbin/postsuper: error while loading shared libraries: libldap-2.2.so.7: cannot open shared object file: No such file or directory /opt/zimbra/postfix-2.2.5/sbin/postalias: error while loading shared libraries: libldap-2.2.so.7: cannot open shared object file: No such file or directory /opt/zimbra/postfix-2.2.5/sbin/postfix: error while loading shared libraries: libldap-2.2.so.7: cannot open shared object file: No such file or directory
Verify that /etc/ld.so.conf contains:
/opt/zimbra/lib /opt/zimbra/sleepycat/lib /opt/zimbra/openldap/lib /opt/zimbra/cyrus-sasl/lib
then run ldconfig (as root).
Mac OS X
Mac OS X ships with Java (so Zimbra does not include it for Mac releases), but the default version - even if 1.5 is installed - is 1.4.
Check the default: ls -l /usr/bin/java.
Check whether 1.5 is installed here: /System/Library/Frameworks/JavaVM.framework/Versions/.
If not, download it from Apple. Once it's installed, you can specify the preferred order of the versions in the Java Application Settings of the Java Preferences utility found in /Applications/Utilities/Java/J2SE 5.0.
You can also make /usr/bin/java a symlink to /System/Library/Frameworks/JavaVM.framework/Versions/1.5.0/Commands/java but this may break any apps using 1.4.
You can verify that java 1.5 is available to zimbra like this:
su - zimbra java -version