FWIW, V2 FW (20050530) is available for the DLink 502t modem/router used by MTNL TriBand ADSL service.
http://www.dlink.co.in/dlink/drivers/support.asp#
Click on "Firmware" and search for 502t in the list of products displayed and download the file. The file is in .rar format and you need MS Windows to apply the new firmware. The unpacked .exe is a Windows app that uploads the firmware embedded within it. As always, ensure the router and your PC are powered by a functional UPS - to avoid any problems in case of power loss.
This version's web admin interacts well with Firefox unlike V1. It has VPN (and more ...) functionality although I have not checked them out yet.
Caveat emptor - update at your own risk.
-- Arun Khan (knura at yahoo dot com) As I was going up Punch Card Hill, Feeling worse and worser, There I met a C.R.T. And it drop't me a cursor. C.R.T., C.R.T., Phosphors light on you! If I had fifty hours a day I'd spend them all at you. -- Uncle Colonel's Cursory Rhymes