Mass Ringless voicemail drop software

Leave voicemail without ringing the phone. Must be able to use any Hosted Multi Channel SIP provider. Must be multi threaded You must have previous experience on ringless voicemail drop! Here is exact program flow program will launch threads load numbers from a txt file load multichannel and multiple sip accounts then starts to place calls two at a time call one times out 1 sec call two placed at same time goes to voicemail call two leaves a prerecorded voicemail and hangs up .