Please verify how your server is configured. Within the vmxml archive is a file called "info.php". if you installed the scripts, for example,
in the folder "vm" on "www.yourserver.com" type in the following url:
http://www.yourserver.com/vm/info.php
This will output your php configuration. Please mail this to me if possible. You can check yourself if you want: search for safe_mode and register_globls within the ouput of info.php.
You dont need to change register_globals, but safe_mode needs to be set to "off" if its on. Rigtt now i dont know whats the correct procedure to configure apache2 for this cause i dont use right now.
Would it be possible that you create me a user account on your machine and let me check the installation? And/or create me voicemail account with at least one message in it?