Have set up two seperate test boxes. 1st Box with Network Trail on rhel(Centos). After I installed Zimbra and rebooted, the boot process hang
at enabling swap space. After an hour or so I gave up waiting. Was able to ping the box and putty into it. (test box was amd 1200gh with 1gb ram. Couldn`t close the boot screen. Eventually (after serveral hours) received a logon screen.
Centos booted fine after initial install it was only after installing zimbra that the boot process hung.

2nd Test box was 2gh amd with 1gh ram. Installed fc4 plus zimbra open. FC4 installed and rebooted fine however after zimbra install this box also hung temporarily after 'enabling swap space' and took about 5-10 to boot to logon page.

Formatted 1st box and installed fc4 and zimbra open and boot process was much quicker though still stalled after 'enabling swap space' (about 5 mins).

Just like to let you know about the issue. Perhaps its the amd cpu,s ?