Methods and systems for processing a signaling message are disclosed. An exemplary method comprises: determining a first transcoding policy (330A) associated with an originator endpoint (320A) contained in a received first call offer (410); determining a second transcoding policy (33OB) associated with an answerer endpoint (330D) contained in the first call offer (410); applying the first transcoding policy (330A) to a first offer codec set in the first call offer (410) to produce a second call offer (420) containing a second offer codec set; applying the second transcoding policy (330B) to the second codec set to produce a third call offer (430) containing a third offer codec set; comparing a first answerer codec set in a received first answer (440) and a second answerer codec set contained in the second call offer (420); and determining whether or not to perform transcoding based on a result of the comparison.