sorry raul..
my english not too good

I'm just give him an advise to use text with good CAPS in this forum . About his project I think he can use the DTMF decoder / encoder on the MCS unit to read the number dialed from the telp device and then connecting the other that called. About interfacing the telp line signal I guest he can't find at his college library. I think it's a simple project, identify the line that dial ,then know dialed number , finally connect them both.