3Com VCX V7000 Maintenance Manual page 67

(US English). The steps in the example install the G.729a codec and
convert any existing custom prompts and voice mail messages to the
G.729a codec format.
IP Messaging must not be actively processing calls while the
codec_data_convert utility is running.
1 Log in to the primary IP Messaging server using the root account.
2 Enter the following command to switch to the IP Messaging installation
directory:
cd /opt/installtemp
3 Enter the following command to install the G.729a codec:
vcx-install UMS-UK-EN-G729a-SPEAK-1-1.i386.rpm
4 Enter the following command to switch to the directory containing the
codec_data_convert utility:
cd /usr/app/app.dir
5 Enter the following command to run the codec_data_convert utility:
./codec_data_convert g711u g729a
If the utility runs successfully, it returns a list of converted files and the
total number of files processed. If the utility fails to run successfully, it
returns an error message and stops further processing.
6 Log in to the secondary IP Messaging server and repeat steps 2 through
5.
Changing Codecs 67