Hi,
I was wrong. Your configuration is correct. after set_body_multipart() msg_appy_changes() is needed
if(has_body("application/sdp")) { set_body_multipart(); if(msg_apply_changes()) { $var(acm) = "7e Od 04 55 75 69 20 4d 61 6b 65 43 61 6c 6c"; append_body_part("$var(acm)","application/isup;version=itu-t92+","signal;handling=optional"); xlog("L_INFO", "ISUP Changes Applied Succesfully"); } }
So please fill the issue at github with all the info in order to be able to dig into this.
Thanks