In order to setup the system to use sound files in a different language (e.g. Spanish):

Interface setup:

• Navigate to 'Settings: Protocols: SIP'
• Set 'Language'='es' (NOTE: This field must be limited to 2 (two) letters)
• Click on the 'Save' button

Directory setup:

• Login to the system via shell as a root user
• Execute 'cd /opt/pbxware/pw/var/lib/asterisk/sounds'
• Execute 'mkdir es'
• Execute 'mkdir ./digits/es'
• Execute mkdir ./letters/es'

Provide sound files:

• Obtain system Spanish sound files
  
• Extract them and put them in the created 'es' directories

• Restart the system from the interface
  

If the Spanish sound file is not found in the 'es' directories, the default system sound file in English will be played back. Also, if the system is multi tenant PBXware and some files wont play for a specific extension, edit that extension and in additional config put:

           language=es