Wireless Tab opens a blank page

Hello,
I have a linksys WRT54G wireless router which I am using from last 3 years. It has a problem of frequently resetting the Wireless security to Unsecure mode. whenever this happens I would loginto the router settings and change the wireless secutity and assign password.
Strangely this time I am not able to open the Wireless tab on the router settings (http://192.168.1.1/wireless.htm). All I see is a blank page and I have no clue how to assign secure key to my router. I have tried removing cache/temporary files from browser and refreshing the page but all I see is a blank page for wireless settings.
Do I need to hard reset my router? Has anybody hacked into my router and disabled its wireless settings permanently? Any help please as I am running my router in unsecure mode.

Thanks
G