Thanks tristanlee85 for starting the thread and till for your solution!
I had exactly the same issue with Centos 5.4 (32bit) install with ISPConfig 3 and had followed exactly the same setup as for the 64bit 5.4 and 32 bit 5.2.
I unistalled bind using yum and uninstalled ISPConfig and re-installed it rather than doing the update (which I'm sure would have worked anyway).
The problem I am still getting (and I'm sure this is only an CentOs issue) is a dovecot issue
Stopping Courier-IMAP server: imap imap-ssl pop3 pop3-ssl
Starting Courier-IMAP server: imap imap-ssl pop3 pop3-ssl
Stopping Dovecot Imap: [FAILED]
Error: Error in configuration file /etc/dovecot.conf line 715: Unknown protocol name (section changed in /etc/dovecot.conf at line 709)
Fatal: Invalid configuration in /etc/dovecot.conf
Starting Dovecot Imap: [FAILED]
Stopping httpd: [ OK ]
[Mon Mar 15 16:52:32 2010] [warn] NameVirtualHost *:80 has no VirtualHosts
Starting httpd: [ OK ]
Stopping pure-ftpd: [ OK ]
Starting pure-ftpd: [ OK ]
I dont mean to hijack your thread tristanlee85