Just done a .tar (not iso) install of Trixbox 1.1 on a new Centos 4.3 server.
Managed to get it going after lots of hassle - I had to download and recompile the zap modules and also download FreePBX because the default install would not work (blank admin web page for a start).
It’s early days but everything I have tested is work OK, except that when I create a new SIP extension and turn on its voicemail, FreePBX doesn’t create the /var/spool/asterisk/voicemail/default/[extn] folder set, but if I do this manually, voicemail seems to work OK.
The file/folder permissions look OK - everything is owned by asterisk:asterisk and the user/group has rwx permissions.
FreePBX is Version 2.1.1 and Voicemail module is 1.1.2.
I just has a brainwave and checked php.ini to make sure that enough memory was being given to the code, but memory_limit is set to 64MB.
I have tried uninstalling and deleting the module and putting it back without luck.