Help required with Asus WL-520GU wireless router

[pnreddy]

I had flashed the dd-wrt fw onto my Asus WL-520 GU wireless router. I have been using it for more than a year without a problem. When I wanted to change some settings, I found that I am unable to log in as I forgot the username and password. I tried the reset button and tried to login as "root"/"root". But I am unable to login. I would appreciate it if some one can help me how to log in to my router. TIA