It doesn't need to. Just tell the Customer care that you're accessing the internet from Linux and you downloaded the latest dialer from their site and it is not working. He/She will do the needful so that you can use the old protocol to connect.
First of all I dont understand why Sify blocks ports for Linux os.I mean if you have linux os and plan to use internet using sify bb you have to call them and ask them to release your ip address for linux and then only your sify net will work on linux.Secondly even after configuring linux os for sifybb it mostly dont work...so the most funny way that I discovered was to connect sify broad band on my dual boot system which has linux as well as windows on it and then logging on to your sify user id on windows and then after sometime remove the ethernet lan wire from the ethernet card, and just reboot your pc into your linux os and the net is working well thats a silly encounter that I had and it works quiet well too for me and does not get disconnected too.Hope sify improves its linux services and I might as well try antidialer.
Well it's not quite blocking ports for Linux. It's more like using a new dialer protocol by default which has not been implemented on Linux. Also, it's a bit strange that your connection is not working despite the CC releasing your MAC address/IP from their list. How did you test for it? Did you use their client (sifyconnect)? Remember that you need to use it in superuser mode.