Another Time Capsule question: Before I got my TC, I was using a regular external USB drive as my Time Machine backup drive. I actually want to keep using this drive for Time Machine, but attach it to my TC so it's wireless. Then I'll use my TC's drive just for storage. I attached it, and Time Machine lets me select this drive as a backup drive. However, it doesn't recognize that I already have Time Machine backups on this drive. So it tells me the drive only has 7gb free and it can't backup. Is there a way to make TM recognize that this drive already has old backups on it and continue doing incremental backups on it? If not, I suppose I'll just format the drive and start with a clean backup and lose my old backup history (not a big deal really).