[asterisk-users] Answer Machine/Fax/modem detection

[Tong]

Has anyone sucessfully implimented a fax or modem detection dial plan?  I'm originating calls from asterisk using a list of numbers and dropping the destination into an IVR menu but need to do something different if a modem or fax answers.  I tried to use the NVBackgroundDetect() application but i think that is for receiving faxes only.  Any help would be appreciated.  

Thanks