B.140. Zapateller()

Generates the "Special Information Tone" to block advance dialing telemarketing systems.
Zapateller(options)
Generates the "Special Information Tone" to indicate the number is not valid or reachable. Some predictive dialing systems will automatically delete a number from the calling list if they receive this tone.
The following "|"-delimited options are accepted:
answer
Answers the line before playing the tone sequence.
nocallerid
Plays the tone only if no caller ID information is received.
[incoming]
; Play the SIT sequence if no caller ID is present:
exten => s,1,Zapateller(nocallerid)
exten => s,n,Wait(3)
exten => s,n,Answer()

Note

Internal help for this application in Asterisk 1.4:
  -= Info about application 'Zapateller' =- 

[Synopsis]
Block telemarketers with SIT

[Description]
  Zapateller(options):  Generates special information tone to block
telemarketers from calling you.  Options is a pipe-delimited list of
options.  The following options are available:
'answer' causes the line to be answered before playing the tone,
'nocallerid' causes Zapateller to only play the tone if there
is no callerid information available.  Options should be separated by |
characters
diff output to internal help in Asterisk 1.2:
- none -