The present invention relates to a method for handling long delays in telecommunication systems, especially in connection with transparent fax services in telecom systems wherein a Global System for Mobile commmunication (GSM) is used, and wherein is used at least one Fax Adaptor/Inter Working Function (FA/IWF), and for the purpose of improving such a telecom system in relation to prior art solutions, it is according to the present invention suggested that said method involves changes in said at least one FA/IWF only. More specifically, the method involves sending of T.30 signals (command or response) towards either of the communication links, only when the associated algorithm has detected a safe period.