Updating an existing channel

I am about to update an existing channel which was published a couple of years ago by some client, I just need to update the existing channel to a new version. While going through the docs http://sdkdocs.roku.com/display/sdkdoc/Packaging+Your+Application , it states that genkey utility should be run for the first time, and for the subsequent updates to the channel, same key should be used, for which the password used while generating the key for the first time is required ( "Whenever you update your application, you should reuse the same key. This can only be done if you have the original password, so it is important to keep the password somewhere safe even after you have finished packaging your application"). Is it mandatory to have the original password ? Sorry I am very new to publishing and am trying to figure out things as I do them, any help will be highly appreciated
Regards,
batheja sumeet.