[OpenSER-Users] Timeout between 100 and 180/183 Messages

I know fr_timer controls the timeout for provisional responses, and fr_inv_timer controls the timeout for final responses. Also, the TM Module documentation explains: "fr_timer - this timer is used when no response was received yet. If there is no response after fr_timer seconds the timer triggers (and failure route will be executed if t_on_failure() was called). If a provisional response was received, the timer is set to fr_inv_timer for INVITE transactions, and RT_T2 for all other transactions. If a final response is received, the transaction has finished." I understand this "If a provisional response was received, the timer is set to fr_inv_timer for INVITE", but how can I set a different timeout for cases when I have received 100 Trying and I didn't get a 180/183 Ringing? This is the example mentioned in documentation: "For example: You want to have fail over if there is no provisional response after 3 seconds, but you want to ring for 60 seconds. Thus, set the fr_timer to 3 and fr_inv_timer to 60." How can I get a fail over if there is no provisional response after 3 seconds, a fail over if there is no 180/183 message after receiving 100 Trying of 10 seconds, and I want the SIP client rings for only 60 seconds? I'll appreciate any help Dioris Moreno