No, I highly doubt that. Clockwork would have let you know before it made the backup or during the making of it. Here is another option for you. I made a 2.1 stock nandroid for people to use if they ever got into a sticky situation. I know it works because me and plenty of others have used it. Here is the link
Stock Roms | Droid Fiend . What you're going to need to do with this is download the file, unzip it and take the backup and put it on your sd card in clockwork/backup folder. Then once it's in the clockwork/backup folder go into recovery and restore the backup like you would do if you made it yourself. This will bring you back to 2.1 stock rooted.