I'd like to add something to Furry's comments: reset your configuration to factory settings prior to doing the 1.22NA upgrade and DO NOT try to restore the settings from a "gateway settings" file created with the prior firmware--go through the trouble to set everything up again. A failed restore can cause silent damage to the router's config (but should be repairable by another factory reset).
If your security software (for example, Windows Live OneCare used to do this) is trying to hack into your router's web configuration (you should see security logs indicating failed attempts), disable it, especially while you are configuring your newly-upgraded router..and changing the config password to something not easily guessable.